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Kaur AK, Bala R, Kumari P, Sood S, Singh K. Microwave Assisted Vilsmeier-Haack Reaction on Substituted Cyclohexanone Hydrazones: Synthesis of Novel 4,5,6,7-Tetrahydroindazole Derivatives. LETT ORG CHEM 2019. [DOI: 10.2174/1570178615666180917101637] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Vilsmeier-Haack reaction is one of the most important chemical reactions used for formylation of electron-rich arens. Even though Vilsmeier-Haack reaction was studied on a wide variety of hydrazones of enolizable ketones, literature lacks the examples of the use of 4-substituted cyclohexanones as a substrate. The cyclization potential of hydrazones of cyclic keto compounds is still interested topic of investigation. In the present study, the reaction of various hydrazines with 4-substituted cyclohexanones was proceeded and the resulted hydrazones in crude form were treated with Vilsmeier- Haack reagent using both conventional as well as microwave methods. The reaction of phenyl hydrazine with 4-phenylcyclohexanone yielded the corresponding tetrahydro-1H-carbazole instead of hydrazone during solvent evaporation at 40ºC. By keeping the temperature of water bath to 0ºC, the corresponding hydrazone was isolated in crude form which was immediate treated with POCl3/DMF for 10 min at 90ºC using microwave irradiation method afforded novel 4,5,6,7-tetrahydroindazole derivative. Using this optimized condition, the substrate scope for the synthesis of tetrahydroindazole derivatives was explored and synthesized total 6 final compounds. The microwave assisted synthesis of tetrahydroindazoles from 4-substituted cyclohexanones has been reported for the first time under mild conditions in good yield. Easy work up procedure, high yielding, shortened reaction times, clean and ecofriendly are the main advantages of this protocol.
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Affiliation(s)
- Aneet Kamal Kaur
- Department of Chemistry, Akal College of Basic Sciences, Eternal University, Baru Sahib, District Sirmour, H.P.-173101, India
| | - Renu Bala
- Department of Chemistry, Akal College of Basic Sciences, Eternal University, Baru Sahib, District Sirmour, H.P.-173101, India
| | - Poonam Kumari
- Department of Chemistry, Akal College of Basic Sciences, Eternal University, Baru Sahib, District Sirmour, H.P.-173101, India
| | - Sumit Sood
- Department of Chemistry, Akal College of Basic Sciences, Eternal University, Baru Sahib, District Sirmour, H.P.-173101, India
| | - Karan Singh
- Department of Chemistry, Akal College of Basic Sciences, Eternal University, Baru Sahib, District Sirmour, H.P.-173101, India
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Bala R, Devi V, Singh P, Kaur N, Kaur P, Kumar A, Yadav AN, Singh K. Regioselective Synthesis of Potent 4,5,6,7-Tetrahydroindazole Derivatives via Microwave-assisted Vilsmeier-Haack Reaction and their Antioxidant Activity Evaluation. LETT ORG CHEM 2019. [DOI: 10.2174/1570178615666180919120329] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Background: Tetrahydroindazole, a member of the fused-pyrazole system, is a least studied
class of heterocyclic compounds owing to its scarcity in nature. However, a large number of synthetically
prepared tetrahydroindazoles are known to show a variety of biological activities such as interleukin-
2 inducible T-Cell kinase inhibitors, AMPA receptor positive allosteric modulators, antitumor,
antituberculosis, anti-inflammatory and antimicrobial activities. Vilsmeier-Haack reaction is one of the
most important chemical reactions used for formylation of electron rich arenes. Even though Vilsmeier-
Haack reaction was studied on a wide variety of hydrazones derived from active methylene
compounds, literature lacks the examples of the use of 4-substituted cyclohexanones as a substrate for
the synthesis of 4,5,6,7-tetrahydroindazoles. The study of the reaction of Vilsmeier-Haack reagent with
hydrazones derived from cyclic keto compounds having active methylene has been considered the interested
topic of investigation. In the present study, ethyl cyclohexanone-4-carboxylate was treated
with one equivalent of various hydrazines for two hours and the resulted hydrazones were further
treated with an OPC-VH reagent (Vilsmeier-Haack reagent isolated from phthaloyl dichloride and N,Ndimethylformamide)
afforded 4,5,6,7-tetrahydroindazoles in excellent yields. The synthesized compounds
4a-f and 5a-f were screened for their antioxidant activities using the DPPH radical scavenging
assay. The target compounds were synthesized regioselectively using 4+1 approach in excellent yields.
A number of experiments using both conventional heating as well as microwave irradiation methods
were tried and on comparison, microwave irradiation method was found excellent in terms of easy
work up, high chemical yields, shortened reaction times, clean and, no by-products formation. Some of
the synthesized compounds showed significant antioxidant activity. The microwave assisted synthesis
of 4,5,6,7-tetrahydroindazoles from ethyl cyclohexanone-4-carboxylate has been reported under mild
conditions in excellent yield. Easy work up, high chemical yield, shortened reaction times, clean and
no by-products formation are the major advantages of this protocol. These advantages may make this
method useful for chemists who are interested in developing novel 4,5,6,7-tetrahydroindazole based
drugs.
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Affiliation(s)
- Renu Bala
- Department of Chemistry, Akal College of Basic Sciences, Eternal University, Baru Sahib, District Sirmour, H.P.- 173101, India
| | - Vandana Devi
- Department of Chemistry, Kurukshetra University, Kurukshetra, Haryana-136118, India
| | - Pratibha Singh
- Department of Chemistry, Akal College of Basic Sciences, Eternal University, Baru Sahib, District Sirmour, H.P.- 173101, India
| | - Navjot Kaur
- Department of Chemistry, Akal College of Basic Sciences, Eternal University, Baru Sahib, District Sirmour, H.P.- 173101, India
| | - Pawandeep Kaur
- Department of Chemistry, Akal College of Basic Sciences, Eternal University, Baru Sahib, District Sirmour, H.P.- 173101, India
| | - Anil Kumar
- Department of Chemistry, Akal College of Basic Sciences, Eternal University, Baru Sahib, District Sirmour, H.P.- 173101, India
| | - Ajar Nath Yadav
- Department of Biotechnology, Akal College of Agriculture, Eternal University, Baru Sahib, District Sirmour, H.P.-173101, India
| | - Karan Singh
- Department of Chemistry, Akal College of Basic Sciences, Eternal University, Baru Sahib, District Sirmour, H.P.- 173101, India
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Lu SH, Liu PL, Wong FF. Vilsmeier reagent-mediated synthesis of 6-[(formyloxy)methyl]-pyrazolopyrimidines via a one-pot multiple tandem reaction. RSC Adv 2015. [DOI: 10.1039/c5ra07707a] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Vilsmeier reagent-mediated synthesis of pyrazolopyrimidines.
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Affiliation(s)
- Shi-Han Lu
- School of Pharmacy
- China Medical University
- Taichung 40402
- Taiwan
- Graduate Institute of Pharmaceutical Chemistry
| | - Po-Lin Liu
- Graduate Institute of Pharmaceutical Chemistry
- China Medical University
- Taichung 40402
- Taiwan
| | - Fung Fuh Wong
- School of Pharmacy
- China Medical University
- Taichung 40402
- Taiwan
- Graduate Institute of Pharmaceutical Chemistry
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Selective synthesis of pyrazolo[3,4-d]pyrimidine, N-(1H-pyrazol-5-yl)formamide, or N-(1H-pyrazol-5-yl)formamidine derivatives from N-1-substituted-5-aminopyrazoles with new Vilsmeier-type reagents. Tetrahedron 2013. [DOI: 10.1016/j.tet.2012.11.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Huang YY, Kaneko K, Takayama H, Kimura M, Wong FF. New investigation of Vilsmeier-type reaction using pyrazolones with various amides. Tetrahedron Lett 2011. [DOI: 10.1016/j.tetlet.2011.05.055] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Wong FF, Huang YY. Novel Vilsmeier-type methylenation for synthesis of dipyrazolylmethane derivatives using formamide or N-methylformamide. Tetrahedron 2011. [DOI: 10.1016/j.tet.2011.03.089] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Chen Z, Yang Y, Su W. New Vilsmeier reaction for facile synthesis of 4-phenyl-2,4-dihydrochromeno[4,3-c]pyrazoles with bis(trichloromethyl) carbonate/DMF. JOURNAL OF CHEMICAL RESEARCH 2010. [DOI: 10.3184/030823410x12888867039388] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
An efficient method for the synthesis of 4-phenyl-2,4- dihydrochromeno[4,3-c]pyrazoles via the cyclisation reaction of the easily available flavanone-4-arylhydrazones with Vilsmeier reagent (Bis(trichloromethyl) carbonate /DMF) has been developed.
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Affiliation(s)
- Zhiwei Chen
- Key Laboratory of Pharmaceutical Engineering of Ministry of Education, College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou 310014, P. R. China
| | - Yanyan Yang
- Key Laboratory of Pharmaceutical Engineering of Ministry of Education, College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou 310014, P. R. China
| | - Weike Su
- Key Laboratory of Pharmaceutical Engineering of Ministry of Education, College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou 310014, P. R. China
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Synthesis of highly functionalized oxazines by Vilsmeier cyclization of amidoalkyl naphthols. Tetrahedron Lett 2009. [DOI: 10.1016/j.tetlet.2009.07.051] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Kumar KH, Perumal PT. A novel one‐pot oxidative deformylation of
N
‐formyldihydroquinolines employing ferric chloride hexahydrate. Synthesis of 4‐chloro‐2‐phenylquinolines and 4‐chloro‐2‐(1,3‐diphenyl‐1
H
‐pyrazol‐4‐yl)quinolines. J Heterocycl Chem 2009. [DOI: 10.1002/jhet.5570450248] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Kalvi. Hemanth Kumar
- Organic Chemistry Division, Central Leather Research Institute, Adayar, Chennai‐20, India
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Hemanth Kumar K, Perumal PT. A novel one-pot oxidative cyclization of 2′-amino and 2′-hydroxychalcones employing FeCl3·6H2O–methanol. Synthesis of 4-alkoxy-2-aryl-quinolines and flavones. Tetrahedron 2007. [DOI: 10.1016/j.tet.2007.06.051] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Zhao L, Liang F, Bi X, Sun S, Liu Q. Efficient Synthesis of Highly Functionalized Dihydropyrido[2,3-d]pyrimidines by a Double Annulation Strategy from α-Alkenoyl-α-carbamoyl Ketene-(S,S)-acetals. J Org Chem 2005; 71:1094-8. [PMID: 16438526 DOI: 10.1021/jo0522106] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A convenient and efficient synthesis of highly functionalized dihydropyrido[2,3-d]pyrimidines via a double [5 + 1] annulation strategy starting from easily available alpha-alkenoyl-alpha-carbamoyl ketene-(S,S)-acetals 1 and cheap reagents (NH4OAc, DMF, and POCl3) has been developed. In the first step of the double annulation route, 2-amino-3-carbamoyl-5,6-dihydro-4-pyridones 2 were created in high to excellent yields by a formal [5C + 1N] annulation reaction of ketene-(S,S)-acetals 1 with ammonia (from ammonium acetate). In the second step of the double annulation strategy, the highly functionalized dihydropyrido[2,3-d]pyrimidine derivatives, 7,8-dihydropyrido[2,3-d]pyrimidin-4(3H)-ones 3 (when R1 = aryl) and 7,8-dihydropyrido[2,3-d]pyrimidines 4 (when R1 = H), were constructed, respectively, in fair to good yields by reacting 2 with excessive Vilsmeier reagent (DMF/POCl3). A mechanism involved in the second [5 + 1] annulation step, including a formal [5 + 1] annulation and accompanied chlorovinylation, chloroformylation, amination, and aromatization reactions, is proposed.
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Affiliation(s)
- Lei Zhao
- Department of Chemistry, Northeast Normal University, Changchun 130024, China
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Kumar KH, Muralidharan D, Perumal P. An efficient oxidation of 2-aryl-1,2,3,4-tetrahydro-4-quinolones employing ferric chloride hexahydrate–methanol: synthesis of naturally occurring 4-alkoxy-2-arylquinolines. Tetrahedron Lett 2004. [DOI: 10.1016/j.tetlet.2004.08.144] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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