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Qin C, Koengeter T, Zhao F, Mu Y, Liu F, Houk KN, Hoveyda AH. Z-Trisubstituted α,β-Unsaturated Esters and Acid Fluorides through Stereocontrolled Catalytic Cross-Metathesis. J Am Chem Soc 2023; 145:3748-3762. [PMID: 36720176 PMCID: PMC10075318 DOI: 10.1021/jacs.2c13245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Catalytic cross-metathesis (CM) reactions that can generate trisubstituted alkenes in high stereoisomeric purity are important but remain limited in scope. Here, CM reactions are introduced that generate Z-trisubstituted α-methyl, α,β-unsaturated, alkyl and aryl esters, thiol esters, and acid fluorides. Transformations are promoted by a Mo bis-aryloxide, a monoaryloxide pyrrolide, or a monoaryloxide chloride complex; air-stable and commercially available paraffin tablets containing a Mo complex may also be used. Alkyl, aryl, and silyl carboxylic esters as well as thiol esters and acid fluoride reagents are either purchasable or can be prepared in one step. Products were obtained in 55-95% yield and in 88:12->98:2 Z/E ratio (typically >95:5). The applicability of the approach is highlighted by a two-step conversion of citronellol to an isomintlactone precursor (1.7 g, 73% yield, and 97:3 Z/E) and a single-step transformation of lanosterol acetate to 3-epi-anwuweizic acid (72% yield and 94:6 Z/E). Included are the outcomes of DFT studies, regarding several initially puzzling catalyst activity trends, providing the following information: (1) it is key that a disubstituted Mo alkylidene, generated by a competing homo-metathesis (HM) pathway, can re-enter the productive CM cycle. (2) Whereas in a CM cycle the formation of a molybdacyclobutane is likely turnover-limiting, the collapse of related metallacycles in a HM cycle is probably rate-determining. It is therefore the relative energy barrier required for these steps that determines whether CM or HM is dominant with a particular complex.
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Affiliation(s)
- Can Qin
- Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467, USA
- Supramolecular Science and Engineering Institute, University of Strasbourg, CNRS, 67000 Strasbourg, France
| | - Tobias Koengeter
- Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467, USA
| | - Fengyue Zhao
- College of Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Yucheng Mu
- Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467, USA
| | - Fang Liu
- College of Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - K. N. Houk
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, USA
| | - Amir H. Hoveyda
- Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467, USA
- Supramolecular Science and Engineering Institute, University of Strasbourg, CNRS, 67000 Strasbourg, France
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Ohmori K, Suzuki K. Group-Selective Approaches to Complex Natural Product Synthesis: Three Examples of Diastereotopos-Selective Reactions. Synlett 2021. [DOI: 10.1055/s-0040-1719840] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
AbstractThis Account showcases three diastereotopos-selective reactions exploited in our complex natural syntheses.1 Introduction2 Malyngolide: Hydroalumination of Bisalkynyl tert-Alcohols3 Cavicularin: Acetal Cleavage4 Carthamin: Bromoacetoxylation5 Conclusions
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Antifungal and Ichthyotoxic Sesquiterpenoids from Santalum album Heartwood. Molecules 2017; 22:molecules22071139. [PMID: 28698478 PMCID: PMC6152050 DOI: 10.3390/molecules22071139] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 06/28/2017] [Accepted: 07/04/2017] [Indexed: 11/21/2022] Open
Abstract
In our continuing study on a survey of biologically active natural products from heartwood of Santalum album (Southwest Indian origin), we newly found potent fish toxic activity of an n-hexane soluble extract upon primary screening using killifish (medaka) and characterized α-santalol and β-santalol as the active components. The toxicity (median tolerance limit (TLm) after 24 h at 1.9 ppm) of α-santalol was comparable with that of a positive control, inulavosin (TLm after 24 h at 1.3 ppm). These fish toxic compounds including inulavosin were also found to show a significant antifungal effect against a dermatophytic fungus, Trichophyton rubrum. Based on a similarity of the morphological change of the immobilized Trichophyton hyphae in scanning electron micrographs between treatments with α-santalol and griseofulvin (used as the positive control), inhibitory effect of α-santalol on mitosis (the antifungal mechanism proposed for griseofulvin) was assessed using sea urchin embryos. As a result, α-santalol was revealed to be a potent antimitotic agent induced by interference with microtubule assembly. These data suggested that α-santalol or sandalwood oil would be promising to further practically investigate as therapeutic agent for cancers as well as fungal skin infections.
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Parthasarathy R, Sulochana N. Simple synthesis of sandalwood odorantrac-Osyrol®and its ethoxy homologue. FLAVOUR FRAG J 2015. [DOI: 10.1002/ffj.3287] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Rajasekaran Parthasarathy
- Department of Chemistry, National Institute of Technology; Tiruchirappalli -620 015 Tamil Nadu India
| | - Nagarajan Sulochana
- Department of Chemistry, National Institute of Technology; Tiruchirappalli -620 015 Tamil Nadu India
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Performance evaluation of a versatile multidimensional chromatographic preparative system based on three-dimensional gas chromatography and liquid chromatography-two-dimensional gas chromatography for the collection of volatile constituents. J Chromatogr A 2015; 1417:96-103. [PMID: 26410184 DOI: 10.1016/j.chroma.2015.09.039] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Revised: 09/10/2015] [Accepted: 09/11/2015] [Indexed: 11/23/2022]
Abstract
The present research deals with the multi-collection of the most important sesquiterpene alcohols belonging to sandalwood essential oil, as reported by the international regulations: (Z)-α-santalol, (Z)-α-trans bergamotol, (Z)-β-santalol, epi-(Z)-β-santalol, α-bisabolol, (Z)-lanceol, and (Z)-nuciferol. A versatile multidimensional preparative system, based on the hyphenation of liquid and gas chromatography techniques, was operated in the LC-GC-GC-prep or GC-GC-GC-prep configuration, depending on the concentration to be collected from the sample, without any hardware or software modification. The system was equipped with a silica LC column in combination with polyethylene glycol-poly(5% diphenyl/95% dimethylsiloxane)-medium polarity ionic liquid or β-cyclodextrin based GC stationary phases. The GC-GC-GC-prep configuration was exploited for the collection of four components, by using a conventional split/splitless injector, while the LC-GC-GC-prep approach was applied for three low abundant components (<5%), in order to increase the quantity collected within a single run, by the LC injection of a high sample amount. All target compounds, whose determination is hampered by the unavailability of commercial standards, were collected at milligram levels and with a high degree of purity (>87%).
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Wang M, Fu C, Ma S. Cleavage of oxygen–sulfur double bonds and carbon–sulfur bonds: unusual highly selective electrophilic addition of allenylic sulfoxides. Chem Sci 2013. [DOI: 10.1039/c2sc21920d] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Structure-odor relationships of α-santalol derivatives with modified side chains. Molecules 2012; 17:2259-70. [PMID: 22357322 PMCID: PMC6268821 DOI: 10.3390/molecules17022259] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Revised: 02/16/2012] [Accepted: 02/20/2012] [Indexed: 11/30/2022] Open
Abstract
(Z)-α-Santalol, which has a unique woody odor, is a main constituent of sandalwood essential oil. We investigated the structure-odor relationship of (Z)-α-santalol and its derivatives, focusing on the relationship between the structure of the side chain and the odor of the compounds. Various α-santalol derivatives (aldehydes, formates, and acetates) were synthesized from (Z)- and (E)-α-santalol, which were prepared from (+)-3-bromocamphor through modifications of a reported synthetic route. The Z- and E-isomers of α-santalols have different double-bond configurations in the side chain. Analogues with saturated side chains were also prepared from the corresponding α-santalols, and the odors of the all the prepared compounds were evaluated. We found that the odors of the Z-isomers (woody) were similar to those of the corresponding saturated compounds, but clearly different from the odors of the corresponding E-isomers (odorless, fresh, or fatty). These results indicate that the relative configuration of the side chain with respect to the santalane frame plays an important role in the odor of α-santalol. E-configuration in the side chain eliminates the woody odor character of α-santalol and its examined derivatives, whereas the Z-configuration or saturation of the carbon side chain does not.
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Daramwar PP, Srivastava PL, Priyadarshini B, Thulasiram HV. Preparative separation of α- and β-santalenes and (Z)-α- and (Z)-β-santalols using silver nitrate-impregnated silica gel medium pressure liquid chromatography and analysis of sandalwood oil. Analyst 2012; 137:4564-70. [DOI: 10.1039/c2an35575b] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Kong W, Guo B, Fu C, Ma S. An Efficient Approach to 2-Bromoalken-3-ols by Regioselective Bromohydroxylation Reaction of Simple Allenes with NBS. European J Org Chem 2011. [DOI: 10.1002/ejoc.201001676] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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11
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Hashmi ASK, Häffner T, Rudolph M, Rominger F. Cyclization of 2-Alkynylallyl Alcohols to Highly Substituted Furans by Gold(I)-Carbene Complexes. European J Org Chem 2010. [DOI: 10.1002/ejoc.201001479] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Fehr C, Magpantay I, Vuagnoux M, Dupau P. The Synthesis of (Z)-Trisubstituted Allylic Alcohols by the Selective 1,4-Hydrogenation of Dienol Esters: Improved Synthesis of (−)-β-Santalol. Chemistry 2010; 17:1257-60. [DOI: 10.1002/chem.201002729] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2010] [Indexed: 11/09/2022]
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Negishi EI, Wang G, Rao H, Xu Z. Alkyne elementometalation-Pd-catalyzed cross-coupling. Toward synthesis of all conceivable types of acyclic alkenes in high yields, efficiently, selectively, economically, and safely: "green" way. J Org Chem 2010; 75:3151-82. [PMID: 20465291 PMCID: PMC2933819 DOI: 10.1021/jo1003218] [Citation(s) in RCA: 118] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Palladium-catalyzed cross-coupling reactions, especially those involving Zn, Al, Zr (Negishi coupling), and B (Suzuki coupling), collectively have brought about "revolutionary" changes in organic synthesis. Thus, two regio- and stereodefined carbon groups generated as R(1)M (M = Zn, Al, B, Cu, Zr, etc.) and R(2)X (X = I, Br, OTs, etc.) may now be cross-coupled to give R(1)-R(2) with essentially full retention of all structural features. For alkene syntheses, alkyne elementometalation reactions including hydrometalation (B, Al, Zr, etc.), carbometalation (Cu, Al-Zr, etc.), and haloboration (BX(3) where X is Cl, Br, and I) have proven to be critically important. Some representative examples of highly efficient and selective (>or=98%) syntheses of di-, tri-, and oligoenes containing regio- and stereodefined di- and trisubstituted alkenes of all conceivable types will be discussed with emphasis on those of natural products. Some interesting but undesirable cases involving loss of the initial structural identities of the alkenyl groups are attributable to the formation of allylpalladium species, which must be either tamed or avoided. Some such examples involving the synthesis of 1,3-, 1,4-, and 1,5-dienes will also be discussed.
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Affiliation(s)
- Ei-Ichi Negishi
- Herbert C. Brown Laboratories of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana 47907-2084, USA.
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Muratore A, Clinet JC, Duñach E. Synthesis of Newexo- andendo-3,8-Dihydro-β-santalols and Other Norbornyl-Derived Alcohols. Chem Biodivers 2010; 7:623-38. [DOI: 10.1002/cbdv.200900119] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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15
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The first enantiospecific total synthesis of the 3-oxygenated sarpagine indole alkaloids affinine and 16-epiaffinine, as well as vobasinediol and 16-epivobasinediol. Tetrahedron Lett 2010. [DOI: 10.1016/j.tetlet.2009.12.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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16
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Negishi EI, Huang Z, Wang G, Mohan S, Wang C, Hattori H. Recent advances in efficient and selective synthesis of di-, tri-, and tetrasubstituted alkenes via Pd-catalyzed alkenylation-carbonyl olefination synergy. Acc Chem Res 2008; 41:1474-85. [PMID: 18783256 DOI: 10.1021/ar800038e] [Citation(s) in RCA: 372] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Although generally considered competitive, the alkenylation and carbonyl olefination routes to alkenes are also complementary. In this Account, we focus on these approaches for the synthesis of regio- and stereodefined di- and trisubstituted alkenes and a few examples of tetrasubstituted alkenes. We also discuss the subset of regio- and stereodefined dienes and oligoenes that are conjugated. Pd-catalyzed cross-coupling using alkenyl metals containing Zn, Al, Zr, and B (Negishi coupling and Suzuki coupling) or alkenyl halides and related alkenyl electrophiles provides a method of alkenylation with the widest applicability and predictability, with high stereo- and regioselectivity. The requisite alkenyl metals or alkenyl electrophiles are most commonly prepared through highly selective alkyne addition reactions including (i) conventional polar additions, (ii) hydrometalation, (iii) carbometalation, (iv) halometalation, and (v) other heteroatom-metal additions. Although much more limited in applicability, the Heck alkenylation offers an operationally simpler, viable alternative when it is highly selective and satisfactory. A wide variety of carbonyl olefination reactions, especially the Wittig olefination and its modifications represented by the E-selective HWE olefination and the Z-selective Still-Gennari olefination, collectively offer the major alternative to the Pd-catalyzed alkenylation. However, the carbonyl olefination method fundamentally suffers from more limited stereochemical options and generally lower stereoselectivity levels than the Pd-catalyzed alkenylation. In a number of cases, however, very high (>98%) stereoselectivity levels have been attained in the syntheses of both E and Z isomers. The complementarity of the alkenylation and carbonyl olefination routes provide synthetic chemists with valuable options. While the alkenylation involves formation of a C-C single bond to a CC bond, the carbonyl olefination converts a CO bond to a CC bond. When a precursor to the desired alkene is readily available as an aldehyde, the carbonyl olefination is generally the more convenient of the two. This is a particularly important factor in many cases where the desired alkene contains an allylic asymmetric carbon center, since alpha-chiral aldehydes can be prepared by a variety of known asymmetric methods and readily converted to allylically chiral alkenes via carbonyl olefination. On the other hand, a homoallylically carbon-branched asymmetric center can be readily installed by either Pd-catalyzed isoalkyl-alkenyl coupling or Zr-catalyzed asymmetric carboalumination (ZACA reaction) of 1,4-dienes. In short, it takes all kinds to make alkenes, just as it takes all kinds to make the world.
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Affiliation(s)
- Ei-ichi Negishi
- H. C. Brown Laboratories of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana 47907-2084
| | - Zhihong Huang
- H. C. Brown Laboratories of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana 47907-2084
| | - Guangwei Wang
- H. C. Brown Laboratories of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana 47907-2084
| | - Swathi Mohan
- H. C. Brown Laboratories of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana 47907-2084
| | - Chao Wang
- H. C. Brown Laboratories of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana 47907-2084
| | - Hatsuhiko Hattori
- H. C. Brown Laboratories of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana 47907-2084
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Parai MK, Shagufta, Srivastava AK, Kassack M, Panda G. An unexpected reaction of phosphorous tribromide on chromanone, thiochromanone, 3,4-dihydro-2H-benzo[b]thiepin-5-one, 3,4-dihydro-2H-benzo[b]oxepin-5-one and tetralone derived allylic alcohols: a case study. Tetrahedron 2008. [DOI: 10.1016/j.tet.2008.07.106] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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18
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Yasui Y, Takeda H, Takemoto Y. Toward General Access to the Aspidosperma-Type Terpenoid Indole Alkaloids: Synthesis of the Key 3,3-Disubstituted Piperidones through Enantioselective Intramolecular Heck-Type Reaction of Chloroformamides. Chem Pharm Bull (Tokyo) 2008; 56:1567-74. [DOI: 10.1248/cpb.56.1567] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Yoshizumi Yasui
- Graduate School of Pharmaceutical Sciences, Kyoto University
| | - Hiroshi Takeda
- Graduate School of Pharmaceutical Sciences, Kyoto University
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An expedient, facile and simple one-pot synthesis of 2-methylenealkanoates and alkanenitriles from the Baylis–Hillman bromides in aqueous media. Nat Protoc 2007; 2:2665-76. [DOI: 10.1038/nprot.2007.369] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Gu Z, Wang X, Shu W, Ma S. Palladium Acetate-Catalyzed Cyclization Reaction of 2,3-Allenoic Acids in the Presence of Simple Allenes: An Efficient Synthesis of 4-(1‘-Bromoalk-2‘(Z)-en-2‘-yl)furan-2(5H)-one Derivatives and the Synthetic Application. J Am Chem Soc 2007; 129:10948-56. [PMID: 17691784 DOI: 10.1021/ja072790j] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We have realized a cyclization reaction of 2,3-allenoic acids 1 in the presence of simple alkyl- or aryl-substituted allenes 3. In this reaction, the cyclic oxypalladation of 2,3-allenoic acid with Pd(II) would afford the furanonyl palladium intermediate 2, which could be trapped by the simple allene to afford a pi-allylic intermediate anti-9. This intermediate anti-9 could be nucleophilically attacked by Br- to yield 4-(1'-bromoalk-2'(Z)-en-2'-yl)furan-2(5H)-one derivatives Z-5 and Pd(0). The in-situ formed Pd(0) was efficiently converted to the catalytically active Pd(II) species by benzoquinone in HOAc. The functional groups, such as malonate, acetoxyl, and phthalic amide in allene 3, are tolerable under the current conditions. High efficiency of chirality transfer was observed when optically active 2,3-allenoic acids were used, which reveals that the formation of the intermediates 2 was a highly stereoselective anti-oxypalladation process. The highly selective formation of Z-isomer may be explained by face-selective coordination of allene 3 with the palladium atom in intermediate 2: the palladium atom coordinates to the terminal C=C double bond of allene 3 from the face opposite to the substituent group to avoid the steric congestion. The products Z-5 could be further elaborated via the S(N)2 nucleophilic substitution with amine or sodium benzenesulfinate, the reduction of the C-Br bond by NaBH(4), and the CuBr.SMe(2)-catalyzed S(N)2'-substitution with CH(3)MgBr.
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Affiliation(s)
- Zhenhua Gu
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Lu, Shanghai 200032, People's Republic of China
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Kim TH, Ito H, Hatano T, Takayasu J, Tokuda H, Nishino H, Machiguchi T, Yoshida T. New antitumor sesquiterpenoids from Santalum album of Indian origin. Tetrahedron 2006. [DOI: 10.1016/j.tet.2006.04.072] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Synthesis and characterization of new difunctional alkynylated (η6-arene)(η4-cycloocta-1,5-diene)ruthenium(0) complexes as molecular models for organometallic polymers. J Organomet Chem 2006. [DOI: 10.1016/j.jorganchem.2006.01.058] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Kim TH, Ito H, Hayashi K, Hasegawa T, Machiguchi T, Yoshida T. Aromatic Constituents from the Heartwood of Santalum album L. Chem Pharm Bull (Tokyo) 2005; 53:641-4. [PMID: 15930775 DOI: 10.1248/cpb.53.641] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A phytochemical investigation of the polar constituents in the heartwood of Indian Santalum album L. resulted in the isolation of three new neolignans (1-3) and a new aromatic ester (4), along with 14 known components. The structures of the new compounds (1-4) were established using spectroscopic methods.
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Affiliation(s)
- Tae Hoon Kim
- Faculty of Pharmaceutical Sciences, Okayama University, Tsushima, Okayama 700-8530, Japan
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Paquette LA, Chang J, Liu Z. Synthetic Studies Aimed at (−)-Cochleamycin A. Evaluation of Late-Stage Macrocyclization Alternatives. J Org Chem 2004; 69:6441-8. [PMID: 15357606 DOI: 10.1021/jo049084a] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An efficient route to the fully functionalized ABC ring systems of the unnatural enantiomer of cochleamycin A was developed. L-(-)-Malic and L-(-)-ascorbic acids served well as starting materials for the two building blocks used to construct an (E,Z,E)-1,6,8-nonatriene intermediate. The AB part structure was assembled by way of a stereocontrolled intramolecular Diels-Alder cycloaddition via adoption of an endo transition state. From this vantage point, two general pathways were subsequently explored as to their suitability for elaboration of the CD rings. Initially examined was a protocol involving 10-membered carbocycle construction. When this approach was demonstrated not to be workable, attention was directed to 10-membered macrolactonization as an alternative tactic. Although assembly of the C-ring in this manner was easily achieved, ultimate closure of the six-membered ring to form ring D remains an unsolved problem.
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Affiliation(s)
- Leo A Paquette
- Evans Chemical Laboratories, The Ohio State University, Columbus, Ohio 43210, USA.
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Nakatsu S, Gubaidullin AT, Mamedov VA, Tsuboi S. A convenient synthesis of olefins via deacylation reaction. Tetrahedron 2004. [DOI: 10.1016/j.tet.2004.01.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Zhao S, Liao X, Wang T, Flippen-Anderson J, Cook JM. The enantiospecific, stereospecific total synthesis of the ring-A oxygenated sarpagine indole alkaloids (+)-majvinine, (+)-10-methoxyaffinisine, and (+)-N(a)-methylsarpagine, as well as the total synthesis of the alstonia bisindole alkaloid macralstonidine. J Org Chem 2003; 68:6279-95. [PMID: 12895062 DOI: 10.1021/jo030055u] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The first stereospecific, enantiospecific total synthesis of the ring-A oxygenated sarpagine indole alkaloids (+)-N(a)-methylsarpagine (8), (+)-majvinine (14), and (+)-10-methoxyaffinisine (49), as well as the first total synthesis of the Alstonia bisindole alkaloid macralstonidine (9), has been accomplished. This approach employed the Schöllkopf chiral auxiliary for the stereospecific construction of the desired d-(+)-tryptophan unit required for the asymmetric Pictet-Spengler reaction. In addition, the strategy was doubly convergent for the enolate-mediated Pd(0) coupling process and the asymmetric Pictet-Spengler reaction can be employed to synthesize both macroline (2) and N(a)-methylsarpagine (8), the coupling of which provides macralstonidine (9). This approach to ring-A substituted alkoxyindole alkaloids should find wide application for the synthesis of other alkaloids for it is stereospecific and either enantiomer can be prepared with ease.
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Affiliation(s)
- Shuo Zhao
- Department of Chemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, USA
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27
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Rivard M, Guillen F, Fiaud JC, Aroulanda C, Lesot P. Efficient enantiodiscrimination of chiral monophosphine oxides and boranes by phosphorus coupled 13C NMR spectroscopy in the presence of chiral ordering agents. ACTA ACUST UNITED AC 2003. [DOI: 10.1016/s0957-4166(03)00202-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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28
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Yu J, Wang T, Liu X, Deschamps J, Flippen-Anderson J, Liao X, Cook JM. General Approach for the Synthesis of Sarpagine Indole Alkaloids. Enantiospecific Total Synthesis of (+)-Vellosimine, (+)-Normacusine B, (−)-Alkaloid Q3, (−)-Panarine, (+)-Na-Methylvellosimine, and (+)-Na-Methyl-16-epipericyclivine. J Org Chem 2003; 68:7565-81. [PMID: 14510528 DOI: 10.1021/jo030006h] [Citation(s) in RCA: 119] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The first total synthesis of (+)-Na-methyl-16-epipericyclivine (9) was completed [from d-(+)-tryptophan methyl ester] in an overall yield of 42% (eight reaction vessels). The optical rotation [[alpha]D +22.8 (c 0.50, CHCl3)] obtained on this material confirmed that the reported optical rotation [[alpha]D 0 (c 0.50, CHCl3)]47 was biogenetically unreasonable. The total syntheses of (+)-vellosimine, (+)-normacusine B, (-)-alkaloid Q3, (-)-panarine, and (+)-Na-methylvellosimine are also described. Moreover, a mixed sample (1:1) of synthetic (-)-panarine and natural (-)-panarine yielded only one set of signals in the 13C NMR; this indicated that the two compounds are identical and further confirmed the correct configuration of (+)-vellosimine, (+)-normacusine B, and (-)-alkaloid Q3. In this approach, the key templates, (-)-Na-H,Nb-benzyltetracyclic ketone 15a and (-)-Na-methyl,Nb-benzyltetracyclic ketone 43 were synthesized on multihundred gram scale by the asymmetric Pictet-Spengler reaction and a stereocontrolled Dieckmann cyclization via improved sequences. An intramolecular palladium (enolate-mediated) coupling reaction was employed to introduce the C(19)-C(20) E-ethylidene function in the sarpagine alkaloids for the first time in stereospecific fashion.
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Affiliation(s)
- Jianming Yu
- Department of Chemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, USA
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29
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Basavaiah D, Rao AJ, Satyanarayana T. Recent advances in the Baylis-Hillman reaction and applications. Chem Rev 2003; 103:811-92. [PMID: 12630854 DOI: 10.1021/cr010043d] [Citation(s) in RCA: 1366] [Impact Index Per Article: 65.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Deevi Basavaiah
- School of Chemistry, University of Hyderabad, Hyderabad, 500 046 India
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30
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Wells MB, McConathy JE, White PS, Templeton JL. Regioselective and Stereoselective Reactions of 2-Butyne Bound to a Resolved Chiral Tungsten(II) Center. Organometallics 2002. [DOI: 10.1021/om020416g] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Michael B. Wells
- Departments of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599-3290, and Campbell University, Buies Creek, North Carolina 27506
| | - Jonathan E. McConathy
- Departments of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599-3290, and Campbell University, Buies Creek, North Carolina 27506
| | - Peter S. White
- Departments of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599-3290, and Campbell University, Buies Creek, North Carolina 27506
| | - Joseph L. Templeton
- Departments of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599-3290, and Campbell University, Buies Creek, North Carolina 27506
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31
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Kotha S, Sreenivasachary N, Brahmachary E. Synthesis of benzocycloheptene-based amino acid derivatives via a [4+2] cycloaddition reaction as a key step. Tetrahedron 2001. [DOI: 10.1016/s0040-4020(01)00575-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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32
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Basavaiah D, Kumaragurubaran N. The Baylis–Hillman chemistry in aqueous media: a convenient synthesis of 2-methylenealkanoates and alkanenitriles. Tetrahedron Lett 2001. [DOI: 10.1016/s0040-4039(00)01967-5] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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33
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Crocker PJ, Saha B, Ryan WJ, Wiley JL, Martin BR, Ross RA, Pertwee RG, Razdan RK. Development of agonists, partial agonists and antagonists in the Δ8-Tetrahydrocannabinol series. Tetrahedron 1999. [DOI: 10.1016/s0040-4020(99)00849-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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34
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Ilankumaran P, Verkade JG. P(RNCH(2)CH(2))(3)N: Efficient Catalysts for Transesterifications, Acylations, and Deacylations. J Org Chem 1999; 64:3086-3089. [PMID: 11674405 DOI: 10.1021/jo981819m] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Extremely strong nonionic superbases of the type P(RNCH(2)CH(2))(3)N catalyze the transesterification of carboxylic acid esters with high selectivity and yields at 25 degrees C. These bases also catalyze the deacetylation of alcohols under mild conditions in quantitative yields. Using enol acetates as acylating agents, primary and secondary alcohols are efficiently protected as acetates through the action of these catalysts. Substituents such as epoxide, carbamate, acetal, oxazoline, nitro, and alkynyl functionalities are tolerated under the reaction conditions. N-Protected peptides undergo clean transesterification without significant racemization, making this methodology potentially very useful.
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35
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Concise synthesis of the bicyclic core of the chromoprotein antibiotics kedarcidin and neocarzinostatin by transannular reductive cyclization of a tetrayne precursor. Tetrahedron Lett 1998. [DOI: 10.1016/s0040-4039(98)02279-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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36
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37
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Denmark SE, Thorarensen A. Tandem [4 + 2]/[3 + 2] Cycloadditions of Nitroalkenes. 11. The Synthesis of (+)-Crotanecine. J Am Chem Soc 1997. [DOI: 10.1021/ja963084d] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Scott E. Denmark
- Contribution from Roger Adams Laboratory, Department of Chemistry, University of Illinois, Urbana, Illinois 61801
| | - Atli Thorarensen
- Contribution from Roger Adams Laboratory, Department of Chemistry, University of Illinois, Urbana, Illinois 61801
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38
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Kuehne ME, Wang T, Seraphin D. Syntheses of Strychnos and Aspidospermatan-Type Alkaloids. 8. Selective Total Syntheses of Mossambine and 14-epi-Mossambine by a Radical Cyclization Reaction(1). J Org Chem 1996; 61:7873-7881. [PMID: 11667746 DOI: 10.1021/jo961023s] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Mossambine (6) was obtained by a six-step reaction sequence from the indoloazepine ester 7. Radical cyclization of the tetracyclic vinyl iodide 12a provided a racemic pentacyclic ketone 16E, which could be converted to either enantiomer by condensation with (S or R)-N,S-dimethyl-S-phenylsulfoximine and selective pyrolysis of the resulting diastereomeric alcohols 18 and 19 or 20 and 21. Selective reductions of the resolved (or racemic) ketone 16E provided mossambine (6) and its hydroxy epimer 17.
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Affiliation(s)
- Martin E. Kuehne
- Department of Chemistry, University of Vermont, Burlington, Vermont 05405
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39
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Luker T, Whitby RJ. Organozirconium methods for the efficient construction of the bicyclo[9.3.0]tetradecane dolabellane skeleton. Tetrahedron Lett 1996. [DOI: 10.1016/0040-4039(96)01707-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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40
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Yamashita K, Sato F. Highly efficient synthesis of allylic alcohols having an α-alkoxyalkyl group at their β-position via regioselective addition reaction of titanium-propargyl ether complexes with carbonyl compounds. Tetrahedron Lett 1996. [DOI: 10.1016/0040-4039(96)01647-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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41
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Kuehne ME, Wang T, Seaton PJ. Total Syntheses of Vincadifformine, 3-Oxovincadifformine, Pseudo- and 20-epi-Pseudovincadifformine, Tabersonine, and Δ18-Tabersonine through Radical Reactions and Heck Reactions. J Org Chem 1996. [DOI: 10.1021/jo960607r] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Martin E. Kuehne
- Department of Chemistry, University of Vermont, Burlington, Vermont 05405
| | - Tiansheng Wang
- Department of Chemistry, University of Vermont, Burlington, Vermont 05405
| | - Pamela J. Seaton
- Department of Chemistry, University of Vermont, Burlington, Vermont 05405
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42
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Ruani F, Yamamura S, Hakomori SI, Igarashi Y. Synthesis of sphingosine conjugate with controlled pore glass beads. Tetrahedron Lett 1995. [DOI: 10.1016/00404-0399(50)1368-r] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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43
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Money T, Wong MK. The use of cyclic monoterpenoids as enantiopure starting materials in natural product synthesis. ACTA ACUST UNITED AC 1995. [DOI: 10.1016/s1572-5995(06)80054-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2023]
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44
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Cruciani P, Aubert C, Malacria M. Studies on diastereoselectivity of the cobalt(I) catalyzed cycloisomerization of substituted ε-acetylenic β-ketoester. Tetrahedron Lett 1994. [DOI: 10.1016/s0040-4039(00)73466-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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45
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46
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Synthesis of deuterated cyclopropene fatty esters structurally related to palmitic and myristic acids. Lipids 1993. [DOI: 10.1007/bf02537081] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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47
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48
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49
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Sato Y, Watanabe S, Shibasaki M. Further studies on a catalytic asymmetric synthesis of decalin derivatives. Tetrahedron Lett 1992. [DOI: 10.1016/s0040-4039(00)92251-2] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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50
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A novel and convenient method for palladium-catalysed alkoxycarbonylation of aryl and vinyl halides using HCO2R/NaOR system. Tetrahedron Lett 1991. [DOI: 10.1016/s0040-4039(00)92287-1] [Citation(s) in RCA: 79] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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