B. Booth, N. Lawrence, R. Pritchard, Humayan S. Rashid
The title compound and related derivatives are synthesised from enamino(triphenyl)phosphonium salts and borane, and converted into β-aminophosphonium salts and β-aminophosphine oxides containing two chiral centres.
{"title":"Synthesis and X-ray crystal structure of (1S,3R,4S,1′S)-4-methyl-3-triphenyl-pnosphonium-1-[1′-methyl(methyiphenyl)]-2-hydrido-2-borazetidinium bromide—the first example of a four-membered C–B–N–C heterocycle","authors":"B. Booth, N. Lawrence, R. Pritchard, Humayan S. Rashid","doi":"10.1039/C39950000287","DOIUrl":"https://doi.org/10.1039/C39950000287","url":null,"abstract":"The title compound and related derivatives are synthesised from enamino(triphenyl)phosphonium salts and borane, and converted into β-aminophosphonium salts and β-aminophosphine oxides containing two chiral centres.","PeriodicalId":17282,"journal":{"name":"Journal of The Chemical Society, Chemical Communications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80417069","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
W. Clegg, R. Errington, K. Fraser, S. Holmes, A. Schäfer
In reactions between the hexamolybdate [Mo6O19]2– and 1,4-diaminobenzene, terminal oxides are replaced by 4-aminophenylimido ligands and the first structurally characterised polyoxometallate to contain functionalised organoimido ligands, (Bun4)2[Mo6O17(NC6H4NH2)2]5, is also the first example of a trans-bis(imido) derivative; further condensation also occurs to yield species in which hexamolybdate units are linked by 1,4-phenylenediimido bridges.
{"title":"Functionalisation of [Mo6O19]2– with aromatic amines: synthesis and structure of a hexamolybdate building block with linear difunctionality","authors":"W. Clegg, R. Errington, K. Fraser, S. Holmes, A. Schäfer","doi":"10.1039/C39950000455","DOIUrl":"https://doi.org/10.1039/C39950000455","url":null,"abstract":"In reactions between the hexamolybdate [Mo6O19]2– and 1,4-diaminobenzene, terminal oxides are replaced by 4-aminophenylimido ligands and the first structurally characterised polyoxometallate to contain functionalised organoimido ligands, (Bun4)2[Mo6O17(NC6H4NH2)2]5, is also the first example of a trans-bis(imido) derivative; further condensation also occurs to yield species in which hexamolybdate units are linked by 1,4-phenylenediimido bridges.","PeriodicalId":17282,"journal":{"name":"Journal of The Chemical Society, Chemical Communications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80499043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Theoretical calculations (G2 with complete optimization of the geometry) of tetrahedrane and its protonated form lead to the conclusion that tetrahedtane should be a superbase [proton affinity (PA) at 298 K, 252.0 kcal mol–1(1 cal = 4.184 J)]; the performance of the G2 method was checked against 14 experimental PA values.
四面体及其质子化形式的理论计算(G2,几何结构完全优化)得出结论:四面体应为超碱[298 K时的质子亲和(PA), 252.0 kcal mol-1 (1 cal = 4.184 J)];通过14个实验PA值检验G2法的性能。
{"title":"Harnessing steric strain to obtain superbases","authors":"R. Notario, J. Elguero","doi":"10.1039/C39950001543","DOIUrl":"https://doi.org/10.1039/C39950001543","url":null,"abstract":"Theoretical calculations (G2 with complete optimization of the geometry) of tetrahedrane and its protonated form lead to the conclusion that tetrahedtane should be a superbase [proton affinity (PA) at 298 K, 252.0 kcal mol–1(1 cal = 4.184 J)]; the performance of the G2 method was checked against 14 experimental PA values.","PeriodicalId":17282,"journal":{"name":"Journal of The Chemical Society, Chemical Communications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79450177","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Pettit, Y. Ichihara, G. Wurzel, Michael D. Williams, Jean M. Schmidt, J. Chapuis
The Micronesian marine sponge Phakellia sp. has been found to contain key members of the extraordinarily potent (antineoplastic) halichondrin/halistatin polyether macrolide family.
{"title":"Isolation and structure of halistatin 3 from the Western Pacific (Chuuk) marine sponge Phakellia sp","authors":"G. Pettit, Y. Ichihara, G. Wurzel, Michael D. Williams, Jean M. Schmidt, J. Chapuis","doi":"10.1039/C39950000383","DOIUrl":"https://doi.org/10.1039/C39950000383","url":null,"abstract":"The Micronesian marine sponge Phakellia sp. has been found to contain key members of the extraordinarily potent (antineoplastic) halichondrin/halistatin polyether macrolide family.","PeriodicalId":17282,"journal":{"name":"Journal of The Chemical Society, Chemical Communications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81277968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
L. Molina, A. Perani, M. Infante, M. Manresa, M. Maugras, S. Achilefu, M. Stébé, C. Selve
Selective activation of 3-hydroxy-2-hydroxymethyl-2-methyl propanamide with P(NMe2)3–CCl4, and subsequent intramolecular cyclisation yields β-lactam derivatives that have both surface and antibiotic activity.
{"title":"Bioactive surfactants containing a β-lactam group: synthesis and properties","authors":"L. Molina, A. Perani, M. Infante, M. Manresa, M. Maugras, S. Achilefu, M. Stébé, C. Selve","doi":"10.1039/C39950001279","DOIUrl":"https://doi.org/10.1039/C39950001279","url":null,"abstract":"Selective activation of 3-hydroxy-2-hydroxymethyl-2-methyl propanamide with P(NMe2)3–CCl4, and subsequent intramolecular cyclisation yields β-lactam derivatives that have both surface and antibiotic activity.","PeriodicalId":17282,"journal":{"name":"Journal of The Chemical Society, Chemical Communications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81285890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A study of hydride nucleophile reactions with η6-(2R, 5R)-dimethylpyrrolidinylbenzene–manganese tricarbonyl hexafluorophosphate 1 reveals an unexpected reversal of selectivity during addition of hydride to the diastereotopic meta carbons, which is explained on the basis of changes in transition state location as the reactivity of the nucleophile is varied.
{"title":"Observations on selectivity reversal during chiral auxiliary-directed asymmetric nucleophile additions to arene–manganese tricarbonyl complexes","authors":"A. Pearson, M. Milletti, P. Zhu","doi":"10.1039/C39950000853","DOIUrl":"https://doi.org/10.1039/C39950000853","url":null,"abstract":"A study of hydride nucleophile reactions with η6-(2R, 5R)-dimethylpyrrolidinylbenzene–manganese tricarbonyl hexafluorophosphate 1 reveals an unexpected reversal of selectivity during addition of hydride to the diastereotopic meta carbons, which is explained on the basis of changes in transition state location as the reactivity of the nucleophile is varied.","PeriodicalId":17282,"journal":{"name":"Journal of The Chemical Society, Chemical Communications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81574987","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Mehta, U. Subramanian, A. Pramanik, J. Chandrasekhar, M. Nethaji
Face selectivity in singlet oxygen addition to a rigid polycyclic diene is reversed by sterically neutral 1,4-substitution, an effect attributed to lone pair repulsions induced by out-of-plane bending at the transition state.
{"title":"Singlet oxygen additions to hexacyclo[10.2.1.02,11.04,9.04,14.09,13]pentadeca-5,7-dien-3,10-diones. A remarkable substituent effect on π-face selectivity induced by transition state geometric distortions","authors":"G. Mehta, U. Subramanian, A. Pramanik, J. Chandrasekhar, M. Nethaji","doi":"10.1039/C39950000677","DOIUrl":"https://doi.org/10.1039/C39950000677","url":null,"abstract":"Face selectivity in singlet oxygen addition to a rigid polycyclic diene is reversed by sterically neutral 1,4-substitution, an effect attributed to lone pair repulsions induced by out-of-plane bending at the transition state.","PeriodicalId":17282,"journal":{"name":"Journal of The Chemical Society, Chemical Communications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84301449","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We report the synthesis and single-crystal X-ray structure of a triply interpenetrated cationic framework with a three-dimensional motif that is based upon T-shaped building blocks generated by silver(I) cations and 1 equivalent of 4,4′-bipyridine.
{"title":"Triple interpenetration in [Ag(4,4′-bipyridine)][NO3], a cationic polymer with a three-dimensional motif generated by self-assembly of ‘T-shaped’ building blocks","authors":"F. Robinson, M. Zaworotko","doi":"10.1039/C39950002413","DOIUrl":"https://doi.org/10.1039/C39950002413","url":null,"abstract":"We report the synthesis and single-crystal X-ray structure of a triply interpenetrated cationic framework with a three-dimensional motif that is based upon T-shaped building blocks generated by silver(I) cations and 1 equivalent of 4,4′-bipyridine.","PeriodicalId":17282,"journal":{"name":"Journal of The Chemical Society, Chemical Communications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84516293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
P. Scrimin, P. Tecilla, U. Tonellato, G. Valle, A. Veronese
The ZnII complex of ligand 1a, a derivative of TREN bearing three 3-hydroxyphenyl units at the amines of its arms, acts as a transacylation catalyst of the p-nitrophenyl ester of 4-pyridinecarboxylic acid.
{"title":"A zinc(II)-organized molecular receptor as a catalyst for the cleavage of amino acid esters","authors":"P. Scrimin, P. Tecilla, U. Tonellato, G. Valle, A. Veronese","doi":"10.1039/C39950001163","DOIUrl":"https://doi.org/10.1039/C39950001163","url":null,"abstract":"The ZnII complex of ligand 1a, a derivative of TREN bearing three 3-hydroxyphenyl units at the amines of its arms, acts as a transacylation catalyst of the p-nitrophenyl ester of 4-pyridinecarboxylic acid.","PeriodicalId":17282,"journal":{"name":"Journal of The Chemical Society, Chemical Communications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84868004","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The mechanism of titanocenedichloride-catalysed hydromagnesiation reaction of alkynes with an alkyl Grignard reagent is elucidated and it is revealed that the regiochemistry of the reaction controlled at the step of transmetallation from titanium to magnesium.
{"title":"On the mechanism of titanocenedichloride-catalysed hydromagnesiation of alkynes with alkyl Grignard reagents","authors":"Yuan Gao, F. Sato","doi":"10.1039/C39950000659","DOIUrl":"https://doi.org/10.1039/C39950000659","url":null,"abstract":"The mechanism of titanocenedichloride-catalysed hydromagnesiation reaction of alkynes with an alkyl Grignard reagent is elucidated and it is revealed that the regiochemistry of the reaction controlled at the step of transmetallation from titanium to magnesium.","PeriodicalId":17282,"journal":{"name":"Journal of The Chemical Society, Chemical Communications","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1995-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85114909","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}