Perspectives on COVID-19 Vaccination and Vaccine Passports in a Diverse Urban Adolescent Population: A Youth Participatory Mixed Methods Study

PURPOSE

Disparities in youth COVID-19 vaccine acceptance and uptake have been documented in several countries, yet few studies have explored the attitudes and perceptions underlying vaccine-related decision-making among adolescent populations with unique sociocultural, environmental, and/or structural contexts that may influence vaccine uptake.

METHODS

This study used data from surveys and semistructured interviews collected between January and March 2022 as part of an ongoing community-based research project in two ethnoculturally diverse, lower income neighborhoods of Montreal, Canada. Youth researchers designed and conducted interviews with unvaccinated adolescents, and thematic analysis was employed to explore attitudes and perceptions underlying vaccine-related decisions and opinions about vaccine passports. Survey data were used to describe sociodemographic and psychological determinants of COVID-19 vaccination.

RESULTS

Among 315 survey participants aged 14-17 years, most (74%) were fully vaccinated against COVID-19. Prevalence ranged from 57% among Black adolescents to 91% among South and/or Southeast Asian adolescents (34% difference, 95% confidence interval: 20-49). Qualitative and quantitative findings highlighted several misconceptions about the safety, effectiveness, and necessity of COVID-19 vaccines and adolescents' desire for trusted sources of information to address their concerns. Vaccine passports likely increased uptake, yet adolescents were strongly resistant to the policy, and for some, it may have fueled distrust of government and scientific institutions.

DISCUSSION

Strategies that increase the trustworthiness of institutions and foster genuine partnership with underserved youth may improve vaccine confidence and help ensure an effective, proequity recovery from COVID-19.

The Epidemiology of Young People's Work and Experiences of Violence in Nine Countries: Evidence from the Violence against Children Surveys

Globally, 497 million young people (15-24 years) are in the labour force. The current research on work and violence indicates reciprocal links across the life course. This study draws on data from 35,723 young people aged 13-24 years in the Violence Against Children Surveys (VACS) in nine countries to describe the epidemiology of work in order to explore associations between (1) current work and violence and (2) childhood violence and work in a hazardous site in young adulthood. The prevalence of past-year work among 13-24-year-olds was highest in Malawi: 82.4% among young men and 79.7% among young women. In most countries, young women were more likely to be working in family or domestic dwellings (range: 23.5-60.6%) compared to men (range: 8.0-39.0%), while men were more likely to be working on a farm. Work in a hazardous site was higher among young men compared to women in every country. Among children aged 13-17 years, we found significant positive associations between past-year work and violence among girls in three countries (aORs between 2.14 and 3.07) and boys in five countries (aORs 1.52 to 3.06). Among young people aged 18-24 years, we found significant positive associations among young women in five countries (aORs 1.46 to 2.61) and among young men in one country (aOR 2.62). Associations between childhood violence and past-year work in a hazardous site among 18-24-year-olds were significant in one country among girls and in three countries among boys. Continued efforts are needed to prevent hazardous work, improve work environments, and integrate violence prevention efforts into workplaces.

Using human-centred design to tackle COVID-19 vaccine hesitancy for children and youth: a protocol for a mixed-methods study in Montreal, Canada

INTRODUCTION

To successfully combat COVID-19 vaccine hesitancy and increase uptake, research has demonstrated that interventions are most effective when tailored to meet local needs through active engagement and co-development with communities. This mixed-methods project uses a human-centred design (HCD) approach to understand local perspectives of COVID-19 vaccine hesitancy and develop strategies to enhance vaccine confidence for children and adolescents.

METHODS AND ANALYSIS

Project ECHO (Étude Communautaire sur l'Hésitation vaccinale contre la COVID-19) combines population-based surveys of parents and adolescents with community-based participatory action research to design and pilot strategies to enhance COVID-19 vaccine confidence in two underserved and ethnoculturally diverse neighbourhoods of Montreal, Canada. Two surveys conducted 6 months apart through primary and secondary schools are used to monitor vaccine acceptance and its social determinants among children and youth. Analyses of survey data include descriptive and inferential statistical approaches. Community-led design teams of parents and youth from the two participating neighbourhoods, supported by academic researchers, design thinking experts and community partners, use an HCD approach to: (1) gather data to understand COVID-19 vaccine decision-making among parents and youth in their community and frame a design challenge (inspiration phase); (2) develop an intervention to address the design challenge (ideation phase) and (3) pilot the intervention (implementation phase). Strategies to evaluate the community-led interventions will be co-developed during the implementation phase.

ETHICS AND DISSEMINATION

This study has been approved by the research ethics boards of the Sainte-Justine University Hospital Centre and the University of Montreal. Community design teams will be involved in the dissemination of findings and the design of knowledge translation initiatives that foster dialogue related to COVID-19 vaccination for children and adolescents among community, school and public health stakeholders. Findings will be disseminated through peer-reviewed publications, conference presentations, community forums, policy briefs, and social media content.

Structure–property relationship of donor–acceptor acridones – an optical, electrochemical and computational study

The effect of changing acceptor strength on intramolecular charge transfer absorption and its implication towards organic materials are investigated.

Evaluation of the diagnostic value of immunocytochemistry and in situ hybridization in the pediatric leprosy

Leprosy is characterized by a long and variable incubation period and a chronic clinical course. Diagnosis of leprosy is essentially based on clinical features. Although the majority of cases can be diagnosed clinically yet alternative methods for diagnosis are required especially for early cases. Immunocytochemistry and in situ hybridization can be a valuable tool for diagnosis for early cases. The present study is aimed to assess the diagnostic value of immunocytochemistry and in situ hybridization in cytological specimens and to compare these techniques with Z.N. staining. This prospective study was carried out in 26 patients below 18 years of age of leprosy. Clinical examination of each patient was done and categorized according to IAL. After taking consent, three skin smears was taken, one for Z.N. staining and remaining two for immunocytochemistry and in situ hybridization respectively. Routine skin smear examination by Z.N. staining method confirmed the diagnosis in 4/26 (15.83%) and these belonged to BB, BL category. Immunocytochemistry showed positivity in 10/15 (66.6%) in BT and 72.7% in BB/BL leprosy. Immunocytochemistry improved the diagnosis by 53.85%, and the results were statistically significant (p < 0.01). In situ hybridization showed the positive results in 80% cases of BT leprosy and 90.9% cases of BB/BL leprosy. In situ hybridization improved the diagnosis by 70% in comparison to ZN staining and the results were statistically significant (p < 0.01). This study supports that immunocytochemistry and in situ hybridization enhance the diagnosis of leprosy when compared to routine skin smears stained by Z.N staining. They are important diagnostictoolsfor definitive diagnosis in early as well as established cases of leprosy.

Chelation of molybdenum in Medicago sativa (alfalfa) grown on reclaimed mine tailings

Extraction and analytical procedures were developed from 1999 to 2005 for the chemical investigation of molybdenum (Mo) in aerial portions of alfalfa ( Medicago sativa L.) grown on a reclaimed mine tailings site at the Highland Valley Copper Mine in British Columbia, Canada. The purification procedures were guided by colorimetric analyses specific for Mo. The Mo levels in freeze-dried plant samples exceeded 100 ppm, which is more than 20 times the maximum level recommended for livestock feed. In contrast to previous work, which detected the inorganic molybdate anion (MoO4(2-)) in alfalfa from the site, the present study identified the major pool of Mo as a chelate bound to malic acid in five sources of plant material. However, the inorganic form of Mo was characterized in aqueous tailings samples, but once imbibed by vegetation, the anion was chelated to the alpha-hydroxy organic acid. Synthetic chelates were synthesized to differentiate the Mo-malate complex from the Mo-citrate by 95Mo NMR. Crystal structure of the synthetic Mo-malate determined that the Mo was bound to two malato ligands as Na 2[MoO2(malate) 2] x 5H2O, which confirmed the structure of the isolates deduced by 95Mo NMR. The chelation of Mo at the site may well explain the apparent lack of long-term clinical effects in cattle grazing the site.

Synthetic and Structural Investigations of Monomeric Dilithium Boraamidinates and Bidentate NBNCN Ligands with Bulky N-Bonded Groups

The dilithiated boraamidinate complexes [Li(2)[PhB(NDipp)(2)](THF)(3)] (7a) (Dipp = 2,6-diisopropylphenyl) and [Li(2)[PhB(NDipp)(N(t)Bu)](OEt(2))(2)] (7b), prepared by reaction of PhB[N(H)Dipp][N(H)R'] (6a, R' = Dipp; 6b, R' = (t)Bu) with 2 equiv of (n)BuLi, are shown by X-ray crystallography to have monomeric structures with two terminal and one bridging THF ligands (7a) or two terminal OEt(2) ligands (7b). The derivative 7a is used to prepare the spirocyclic group 13 derivative [Li(OEt(2))(4)][In[PhB(NDipp)(2)](2)] (8a) that is shown by an X-ray structural analysis to be a solvent-separated ion pair. The monoamino derivative PhBCl[N(H)Dipp] (9a), obtained by the reaction of PhBCl(2) with 2 equiv of DippNH(2), serves as a precursor for the synthesis of the four-membered BNCN ring [[R'''N(H)](Ph)B(mu-N(t)Bu)(2)C(n)Bu] (10a, R''' = Dipp). The X-ray structures of 6a, 9a, and 10a have been determined. The related derivative 10b (R''' = (t)Bu) was synthesized by the reaction of [Cl(Ph)B(mu-N(t)Bu)(2)C(n)Bu] with Li[N(H)(t)Bu] and characterized by (1)H, (11)B, and (13)C NMR spectra. In contrast to 10a and 10b, NMR spectroscopic data indicate that the derivatives [[DippN(H)](Ph)B(NR')(2)CR(NR')] (11a: R =( t)Bu, R' = Cy; 11b: R = (n)Bu, R' = Dipp) adopt acyclic structures with three-coordinate boron atoms. Monolithiation of 10a produces the novel hybrid boraamidinate/amidinate (bamam) ligand [Li[DippN]PhB(N(t)Bu)C(n)Bu(N(t)Bu)] (12a).

Preparation of vinylogous 2-sulfonylindolines by the palladium-catalyzed heteroannulation of o-iodoanilines with dienyl sulfones and their further transformation to indoles and carbazoles

The palladium-catalyzed heteroannulation of o-iodoanilines with dienyl sulfones provides a convenient route to vinylogous 2-sulfonylindolines 3. The reaction proceeds in DMF/water in the presence of potassium carbonate and catalytic palladium(II) acetate and is compatible with both electron-donating and -withdrawing substituents in the para position of the aniline, and with an alkyl substituent at C-2 of the dienyl sulfone. The indolines underwent oxidation with DDQ to afford the corresponding indoles 4. The latter were then employed as dienes in Diels-Alder reactions with dimethyl acetylenedicarboxylate (DMAD), methyl propiolate, or methyl acrylate. In the case of the latter two dienophiles, the cycloadditions were highly regioselective, affording the corresponding 1,3-products (with respect to the relative positions of the sulfone and ester groups), exclusively. The cycloadducts from acetylenic dienophiles were converted to the corresponding carbazoles by elimination of the sulfone moiety with DBU, and that from methyl acrylate was subjected to reductive desulfonylation and oxidation to the corresponding carbazole with DDQ. The method thus provides access to carbazoles with various substituents at the 3-, 4-, and 6-positions.

Highly selective guest uptake in a silver sulfonate network imparted by a tetragonal to triclinic shift in the solid state

The silver sulfonate network presented herein, silver 3-pyridinesulfonate, reversibly and selectively absorbs MeCN while undergoing a major structural rearrangement. The origin of this structural flexibility is a coupling of the weak coordinating ability of the SO3 group with the geometrically pliant silver(I) center. Single crystal and powder X-ray structures of both the desolvated and solvated forms are presented in addition to the mechanism of their reversible interconversion. A heterogeneous gas chromatographic study showing selective extraction of the MeCN is also presented. Extended solid frameworks which reorder to any extent are not common but the structure presented herein transforms from a tetragonal to a triclinic crystal system. The results indicate that cooperative interactions in systems based on supposedly weaker interactions can yield softer yet functional networks with behavior unlike that observed in more rigid inorganic frameworks.

A simple resolution procedure using the Staudinger reaction for the preparation of P-stereogenic phosphine oxides

The resolution of a variety of (+/-)-P-stereogenic phosphines is achieved by exploiting the Staudinger reaction of a (+/-)-phosphine with enantiopure (1S,2R)-O-(tert-butyldimethylsilyl)isobornyl-10-sulfonyl azide. The resulting mixtures of diastereomeric phosphinimines are generally separable by fractional crystallization or flash chromatography. Subsequent acid-catalyzed hydrolysis provides the corresponding optically pure phosphine oxides in high yields.

Steric effects on the mode of aggregation and reactivity of clusters formed from the lithiation of trisamidothiophosphates

Lithiation of SP[N(H)R]3 with LiBun produces the dimers [(THF)LiSP(NR)(NHR)2]2 (R = Pri) or ([LiSP(NR)-(NHR)2][(THF)LiSP(NR)2(NHR)])2 (R = But) with central Li2N2 or Li2S2 rings, respectively; further lithiation yields the dianion [SP(NR)2(NHR)]2- (R = Pri) or leads to sulfur extrusion when R = But.

pi-Facial selectivities of diastereotopic ketones: p-bromobenzoates of 4-hetero-1-decalinols

The crystal structures of the p-bromobenzoates of cis-4-oxa-1-decalinyl (C(16)H(19)BrO(3)), trans-4-oxa-1-decalinyl (C(16)H(19)BrO(3)), N-benzyl-cis-4-aza-1-decalinyl (C(23)H(26)BrNO(2)), N-benzyl-trans-4-aza-1-decalinyl (C(23)H(26)BrNO(2)) and trans-4-thia-1-decalinyl (C(16)H(19)BrO(2)S) (decalin is perhydronaphthalene) have been determined as part of a study directed at predicting and interpreting the pi-facial selectivities of diastereotopic ketones in reactions with nucleophiles. All five structures are composed of molecules that are separated by normal van der Waals distances. In all five structures, the heterocyclic and cyclohexyl rings adopt chair conformations, and the p-bromobenzoate groups are planar.

Preparation and x-ray structures of alkali-metal derivatives of the ambidentate anions [tBuN(E)P(mu-NtBu)2P(E)NtBu]2- (E = S, Se) and [tBuN(Se)P(mu-NtBu)2PN(H)tBu)]-

The ambidentate dianions [(t)BuN(E)P(mu-N(t)Bu)(2)P(E)N(t)Bu](2)(-) (5a, E = S; 5b, E = Se) are obtained as their disodium and dipotassium salts by the reaction of cis-[(t)Bu(H)N(E)P(mu-N(t)Bu)(2)P(E)N(H)(t)Bu] (6a, E = S; 6b, E = Se), with 2 equiv of MN(SiMe(3))(2) (M = Na, K) in THF at 23 degrees C. The corresponding dilithium derivative is prepared by reacting 6a with 2 equiv of (t)BuLi in THF at reflux. The X-ray structures of five complexes of the type [(THF)(x)()M](2)[(t)BuN(E)P(mu-N(t)Bu)(2)P(E)N(t)Bu] (9, M = Li, E = S, x = 2; 11a/11b, M = Na, E = S/Se, x = 2; 12a, M = K, E = S, x = 1; 12b, M = K, E = Se, x = 1.5) have been determined. In the dilithiated derivative 9 the dianion 5a adopts a bis (N,S)-chelated bonding mode involving four-membered LiNPS rings whereas 11a,b and 12a,b display a preference for the formation of six-membered MNPNPN and MEPNPE rings, i.e., (N,N' and E,E')-chelation. The bis-solvated disodium complexes 11a,b and the dilithium complex 9 are monomeric, but the dipotassium complexes 12a,b form dimers with a central K(2)E(2) ring and associate further through weak K.E contacts to give an infinite polymeric network of 20-membered K(6)E(6)P(4)N(4) rings. The monoanions [(t)Bu(H)N(E)P(mu-N(t)Bu)(2)P(E)N(t)Bu)](-) (E = S, Se) were obtained as their lithium derivatives 8a and 8b by the reaction of 1 equiv of (n)BuLi with 6a and 6b, respectively. An X-ray structure of the TMEDA-solvated complex 8a and the (31)P NMR spectrum of 8b indicate a N,E coordination mode. The reaction of 6b with excess (t)BuLi in THF at reflux results in partial deselenation to give the monolithiated P(III)/P(V) complex [(THF)(2)Li[(t)BuN(Se)P(mu-N(t)Bu)(2)PN(H)(t)Bu]] 10, which adopts a (N,Se) bonding mode.

Syntheses, structures, and stabilities of [PPh(4)][WS(3)(SR)](R=(i)Bu,(i)Pr,(i)Bu, benzyl, allyl) and [PPh(4)][MoS(3)(S(t)Bu)]

Intermediates in the condensation process of [MS(4)](2)(-) (M = Mo, W) to polythiometalates, in the presence of alkyl halides, had not been reported prior to our communication of [PPh(4)][WS(3)(SEt)] (Boorman, P. M.; Wang, M.; Parvez, M. J. Chem. Soc., Chem. Commun. 1995, 999-1000). We now report the isolation of a range of related compounds, with 1 degrees, 2 degrees, and 3 degrees alkyl thiolate ligands, including one Mo example. [PPh(4)][WS(3)(SR)] (R = (i)Bu (1), (i)Pr (2), (t)Bu (3), benzyl (5), allyl (6)) and [PPh(4)][MoS(3)(S(t)Bu)] (4) have been isolated in fair to good yields from the reaction of [PPh(4)](2)[MS(4)] with the appropriate alkyl halide in acetonitrile and subjected to analysis by X-ray crystallography. Crystal data are as follows: for 1, triclinic space group P1 (No. 2), a = 11.0377(6) A, b = 11.1307(5) A, c = 13.6286(7) A, alpha = 82.941(1) degrees, beta = 84.877(1) degrees, gamma = 60.826(1) degrees, Z = 2; for 2, monoclinic space group P2(1)/c (No. 14), a = 9.499(6) A, b = 15.913(5) A, c = 18.582(6) A, beta = 99.29(4) degrees, Z = 4; for 3, monoclinic space group P2(1)/n (No. 14), a = 10.667(2) A, b = 17.578(2) A, c = 16.117(3) A, beta = 101.67(1) degrees, Z = 4; for 4, monoclinic space group P2(1)/n (No. 14), a = 10.558(3) A, b = 17.477(3) A, c = 15.954(3) A, beta = 101.18(2) degrees, Z = 4; for 5, monoclinic space group P2(1)/n (No. 14), a = 16.2111(9) A, b = 11.0080(6) A, c = 18.1339(10) A, beta = 111.722(1) degrees, Z = 4; for 6, triclinic space group P1 (No. 2), a = 9.4716(9) A, b = 10.4336(10) A, c = 14.4186(14) A, alpha = 100.183(2) degrees, beta = 90.457(2) degrees, gamma = 91.747(2) degrees, Z = 2. Structures 3 and 4 are isomorphous, and 1 exhibits disorder about the tertiary carbon. 6 has been shown to exhibit fluxionality in solution by variable-temperature (1)H NMR studies, and an allyl migration mechanism is implicated in this process. The kinetics for the reaction of [WS(4)](2)(-) and EtBr were measured and suggest an associative nucleophilic substitution (S(N)2) mechanism. The decomposition of the [WS(3)(SEt)](-) ion is shown to be second order with respect to this ion, suggesting the formation of a transient binuclear intermediate. M-S bond cleavage is the predominant step in decomposition of 1-6 to yield alkyl sulfides, alkyl thiols, and polythiometalates such as [PPh(4)](2)[M(3)S(9)]. In contrast, reactions of [PPh(4)](2)[WO(x)()S(4)(-)(x)()] (x = 1, 2) with (t)BuBr result in the additional decomposition product of isobutene, presumably by C-S bond cleavage and beta-hydrogen transfer. Interestingly, the reaction of [PPh(4)](2)[WOS(3)] with BzCl yields 5 as the only isolable W thiolate species.

7-Phenyl-1-oxa-4-thiaspiro[4.5]decan-7-ol stereoisomers

The stereoisomers of 7-phenyl-1-oxa-4-thiaspiro[4.5]decan-7-ol, C(14)H(18)O(2)S, have the same stereochemistry at the C atom bearing an OH group, i.e. axial OH and equatorial phenyl groups. However, the acetal S and O atoms are axial and equatorial, respectively, in one isomer and reversed in the second. Furthermore, the crystals of one isomer are composed of hydrogen-bonded molecules involving the hydroxyl H atom and the O atom of the five-membered heterocyclic ring, with an O.O distance of 2.962 (3) A, forming a polymeric chain along the b axis. The asymmetric unit of the other isomer is composed of two molecules, wherein hydroxyl H atoms and the O atoms of the five-membered heterocyclic rings display intramolecular O-H.O hydrogen bonds with O.O separations of 2.820 (2) and 2.834 (2) A.

Preparation and X-ray structures of Cu(I), Ni(II), and Pd(II) (N,S) complexes of the monoanion [(tBuN)(S)P(mu-N(t)Bu)2P(S)(NH(t)Bu)]- and a Pt(II) (S,S') complex of the dianion [((t)BuN)(S)P(mu-N(t)Bu)2P(S)(N(t)Bu)]2-

The metathetical reactions of the lithium derivative of the monoanion [((t)BuN)(S)P(mu-N(t)Bu)(2)P(S)(NH(t)Bu)](-) (L) with CuCl/PPh(3), NiCl(2)(PEt(3))(2), PdCl(2)L'(2) (L' = PhCN, PPh(3)), and PtCl(2)(PEt(3))(2) produced the complexes (PPh(3))CuL (5), NiL(2) (6), PdCl(L)(PPh(3)) (7), PdL(2) (8), and Pt(PEt(3))(2)[((t)BuN)(S)P(mu-N(t)Bu)(2)P(S)(N(t)Bu)] (9). The X-ray structures of 5, 6, and 8 reveal a N,S-coordination for the chelating monoanion L with the metal centers in trigonal planar, tetrahedral, and square planar environments, respectively. By contrast, the dianionic ligand in the square planar Pt(II) complex 9 is S,S'-chelated to the metal center. (31)P NMR spectra readily distinguish between the N,S and S,S' bonding modes, and, on that basis, N,S chelation is inferred for the Pd(II) complex 7. Crystal data: 5, monoclinic, P2(1)/c, a = 19.175(4) A, b = 20.331(4) A, c = 10.017(6) A, beta = 91.79(3) degrees, V = 3903(2) A(3), and Z = 4; 6, orthorhombic, Pbcn, a = 14.298(5) A, b = 15.333(5) A, c = 24.378(5) A, beta = 90.000(5) degrees, V = 5344(3) A(3), and Z = 4; 8, monoclinic, P2(1)/n, a = 13.975(3) A, b = 14.283(3) A, c = 15.255(4) A, beta = 116.565(18) degrees, V = 2723.5(11) A(3), and Z = 2; 9, monoclinic, P2(1)/n, a = 12.479(6) A, b = 21.782(7) A, c = 17.048(5) A, beta = 100.30(3) degrees, V = 4559(3) A(3), and Z = 4.

Doxylaminium tetrachlorocuprate(II)

The structure of the title compound, 2-[1-(dimethylammonioethoxy)-1-phenylethyl]pyridinium tetrachlorocuprate(II), (C(17)H(24)N(2)O)[CuCl(4)], contains dihydro cations of doxylamine hydrogen bonded to two Cl atoms in two different [CuCl(4)](2-) anions, with Cl...N distances of 3.101 (9) and 3.253 (10) A. The ethereal O atom is involved in intramolecular hydrogen bonds, with O.N distances of 2.517 (11) and 2.757 (12) A. The molecular dimensions in the cation are as expected and the [CuCl(4)](2-) anion has a flattened tetrahedral geometry.

Lithium halide adducts of imidotellurium(IV) ligands: synthesis and X-ray structures of [Li(THF)2L](mu 3-I)[LiI(L)] [L = tBuNTe(mu-NtBu)2TeNtBu] and [(THF)3Li3(mu 3-I)(Te(NtBu)3)]

The reaction of the chelating ligand tBuNTe(mu-NtBu)2TeNtBu (L) with LiI in THF yields [Li(THF)2L](mu 3-I)[LiI(L)] (3). This complex is also formed by the attempted oxidation of [Li2Te(NtBu)3]2 with I2. An X-ray analysis of 3 reveals that the tellurium diimide dimer acts as a chelating ligand toward (a) [Li(THF)2]+ cations and (b) a molecule of LiI. An extended structure is formed via weak Te...I interactions [3.8296(7)-3.9632(7) A] involving both mu 3-iodide counterions and the iodine atoms of the coordinated LiI molecules. Crystal data: 3, triclinic, space group P1, a = 10.1233(9) A, b = 15.7234(14) A, c = 18.8962(17) A, alpha = 86.1567(16) degrees, beta = 84.3266(16) degrees, gamma = 82.9461(16) degrees, V = 2965.8(5) A3, Z = 2. The oxidation by air of [Li2Te(NtBu)3]2 in toluene produces the radical (Li3[Te(NtBu)3]2), which exhibits an ESR spectrum consisting of a septet of decuplets (g = 2.00506, a(14N) = 5.26 G, a(7Li) = 0.69 G). The complexes [(THF)3Li3(mu 3-X)(Te(NtBu)3)] (4a, X = Cl; 4b, X = Br; 4c, X = I) are obtained from the reaction of [Li2Te(NtBu)3]2 with lithium halides in THF. The iodide complex, 4c, has a highly distorted, cubic structure comprised of the pyramidal [Te(NtBu)3]2- dianion which is linked through three [Li(THF)]+ cations to I- Crystal data: 4c, triclinic, space group P1, a = 12.611(8) A, b = 16.295(6) A, c = 10.180(3) A, alpha = 98.35(3) degrees, beta = 107.37(4) degrees, gamma = 108.26(4) degrees, V = 1829(2) A3, Z = 2.

Astemizole tetrachlorocuprate(II)

The structure of ¿3-[(4-fluorophenyl)methyl]-1H-benzimidazol-2-ylidene¿¿1-[2-(4- methox yphenyl)ethyl]-4-piperidin-1-io¿ammonium tetrachlorocuprate(II), (C(28)H(33)FN(4)O)[CuCl(4)], contains diprotonated cations of astemizole hydrogen bonded to three Cl atoms in two different CuCl(4)(2-) anions, with Cl.N distances in the range 3.166 (4)-3.203 (4) A. The geometry around copper is flattened tetrahedral with significantly different Cu-Cl distances which lie in the range 2.1968 (14)-2.2861 (12) A. The phenylethyl C atoms of the (4-methoxyphenyl)ethyl group are disordered indicating the presence of two conformers in the crystals.

Synthesis, resolution, and applications of 2, 2'-bis(diphenylphosphino)-3,3'- binaphtho[2,1-b]furan

[structure: see text] A short five-step synthesis of (+/-)-2,2'-bis(diphenylphosphino)-3, 3'-binaphtho[2,1-b]furan (BINAPFu, 1) starting from 2-naphthoxyacetic acid is reported. The resolution of BINAPFu 1 was possible using our newly developed resolution procedure for phosphines wherein (1S)-camphorsulfonyl azide was used to prepare the bisphosphinimine of BINAPFu via the Staundinger reaction. BINAPFu consistently outperformed BINAP in an asymmetric Heck reaction between 2,3-dihydrofuran and phenyl triflate.

Structure revision of isoline (ruwenine), bisline and isolinecic acid

X-ray crystallography of bisline, and the chemical interconversion of bisline and isoline (ruwenine), revealed that the structures previously assigned to these alkaloids required revision; as did that of isolinecic acid.

Clemizoledichlorocobalt(II)

The structure of dichloro[1-(p-chlorobenzyl)-2-(1-pyrrolidinylmethyl-N)-1, 3-benzimidazole-N(3)]cobalt(II), [CoCl(2)(C(19)H(20)ClN(3))], contains a molecule of clemizole bound in a bidentate manner to cobalt through its imidazole and pyrrolidinyl N atoms, with significantly different Co-N distances of 1.976 (5) and 2.126 (5) A, respectively. The geometry around cobalt is distorted tetrahedral, with significantly different Co-Cl distances of 2.217 (2) and 2.233 (2) A, and the pyrrolidinyl ring is disordered.

Polylithiated tetraaminosilanes: synthesis and characterization of (Et2O.Li)4[Si(Nnaph)4] and X-ray structure of (THF.Li3[Si(NiPr)3(NHiPr)])2

The treatment of SiCl4 with 4 equiv of Li2(Nnaph) (naph = 1-naphthyl) in diethyl ether gives (Et2O.Li)4[Si(Nnaph)4] (4), which, upon reaction with excess tBuNH3Cl or MeO3SCF3, generates Si[N(H)naph]4 (5) or Si[N(Me)naph]4 (6), respectively. The centrosymmetric dimer (THF.Li3[Si(NiPr)3(NHiPr)])2 (7), formed via trilithiation of Si[N(H)iPr]4 with n-butyllithium, consists of a bis-THF-solvated Li6(NiPr)6 cyclic ladder bicapped by two SiN(H)iPr units. Crystal data for 7: C32H74Li6N8O2Si2, monoclinic, P2(1)/n, a = 10.661(7) A, b = 16.964(5) A, c = 12.405(4) A, beta = 93.22(4) degrees, V = 2239.9(15) A3, and Z = 2.

Eight- and 16-membered cyanuric-sulfanuric ring systems: C2N4S2-->C2N3S ring contraction

Eight- and 16-membered cyanuric-sulfanuric ring systems of the type Ar2C2N4S2(O)2Ar'2 (3a, Ar = 4-BrC6H4, Ar' = Ph; 3b, Ar = 4-CF3C6H4, Ar' = Ph; 3c, Ar = 4-CF3C6H4, Ar' = 4-CH3C6H4) and Ar4C4N8S4(O)4Ar'4 (4b, Ar = 4-CF3C6H4, Ar' = Ph; 4c, Ar = 4-CH3C6H4, Ar' = Ph; 4d, Ar = 4-CF3C6H4, Ar' = 4-CH3C6H4), respectively, were prepared in good yields by the reaction of the corresponding sulfur(IV) systems with m-chloroperbenzoic acid. The X-ray structures of 3b, 3c.C7H14, 4b.CH2Cl2, 4c, and the S(IV) system Ar4C4N8S4Ar'4 (2c, Ar = 4-CH3C6H4, Ar' = Ph) were determined. Upon oxidation the two oxygen atoms in 3b and 3c.C7H14 adopt endo positions leading to a twist boat conformation for the C2N4S2 ring. The 16-membered C4N8S4 rings in 4b and 4c retain a cradle conformation upon oxidation. The S-N bond distances are ca. 0.06 A shorter in all the S(VI) systems compared to those in the corresponding S(IV) rings. The thermolysis of 3b at ca. 220 degrees C occurs primarily via loss of a sulfanuric group, NS(O)Ph, to give the six-membered ring (4-CF3C6H4)2C2N3S(O)Ph (6). The structure of 6 was confirmed by X-ray crystallography. Crystal data: 2c, triclinic, space group P1 with a = 13.917(2) A, b = 15.610(4) A, c = 13.491(3) A, alpha = 95.77(2) degrees, beta = 114.82(1) degrees, gamma = 76.21(2) degrees, V = 2583(1) A3, and Z = 2; 3b, monoclinic, space group P2(1)/a with a = 7.316(2) A, b = 29.508(5) A, c = 12.910(2) A, beta = 101.30(2) degrees, V = 2733(1) A3, and Z = 4; 3c.C7H14, triclinic, space group P1 with a = 12.849(4) A, b = 12.863(4) A, c = 12.610(7) A, alpha = 110.61(3) degrees, beta = 105.77(3) degrees, gamma = 62.77(2) degrees, V = 1719(1) A3, and Z = 2; 4b.CH2Cl2, triclinic, space group P1 with a = 12.647(3) A, b = 19.137(3) A, c = 12.550(2) A, alpha = 105.765(11) degrees, beta = 93.610(15) degrees, gamma = 88.877(16) degrees, V = 2917.2(9) A3, and Z = 2; 4c, orthorhombic, space group Pba2 with a = 22.657(2) A, b = 10.570(2) A, c = 10.664(3) A, alpha = beta = gamma = 90 degrees, V = 2554(1) A3, and Z = 2; 6, triclinic, space group P1 with a = 7.4667(8) A, b = 11.3406(12) A, c = 13.5470(14) A, alpha = 108.000(2) degrees, beta = 105.796(2) degrees, gamma = 94.300(2) degrees, V = 1033.8(2) A3, and Z = 2.

Caulerpin

The crystal structure of caulerpin (dimethyl 6,13-dihydrodibenzo[b,i]phenazine-5,12-dicarboxylate, C(24)H(18)N(2)O(4)), an indole alkaloid, reported in space group Cc with an acute beta angle, has been redetermined in the correct space group, C2/c. The molecule has twofold crystallographic symmetry and is composed of two essentially planar indole groups fused to an eight-membered cyclooctatetraene ring which adopts a boat conformation. The molecular dimensions are normal. The structure is stabilized by intermolecular and intramolecular interactions involving the indole N-H atom and carbonyl O atom [N.O 3.211 (4) and 2.836 (4) A].