{"title":"LIII.—The constituents of Indian turpentine from Pinus longifolia, roxb. Part IV","authors":"P. Pillay, J. Simonsen","doi":"10.1039/JR9280000359","DOIUrl":"https://doi.org/10.1039/JR9280000359","url":null,"abstract":"","PeriodicalId":17266,"journal":{"name":"Journal of The Chemical Society (resumed)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76817078","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}
{"title":"CCCXXXVIII.—The atomic weight of antimony from different sources","authors":"K. R. Krishnaswami","doi":"10.1039/JR9270002534","DOIUrl":"https://doi.org/10.1039/JR9270002534","url":null,"abstract":"","PeriodicalId":17266,"journal":{"name":"Journal of The Chemical Society (resumed)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75225864","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}
{"title":"Pigments, mediums, and technical methods of classical and mediæval painters","authors":"A. Laurie","doi":"10.1039/JR9370000163","DOIUrl":"https://doi.org/10.1039/JR9370000163","url":null,"abstract":"","PeriodicalId":17266,"journal":{"name":"Journal of The Chemical Society (resumed)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90596529","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}
J. Maarseveen, Wim J. N. Meester, J. Veerman, C. G. Kruse, P. Hermkens, F. Rutjes, H. Hiemstra
We have evaluated the allyl, 2-sulfonylethyl (SEC) and 2-thioethyl (TEC) carbamate linker systems for their application in solid supported N-acyliminium ion chemistry. As model reactions the syntheses of both homoallylic amines (via a three component protocol starting from an immobilised primary carbamate) and 2-substituted pyrrolidines (via carbamate bound 4,4-diethoxy-2-phenylbutylamine) were conducted. The required precursor p-nitrophenyl carbonate resins were prepared in high yields from cheap starting materials. All linkers proved to be stable under the required cationic reaction conditions. A serious drawback of the allyl carbamate linker is the tedious work up procedure which is required for the removal of the remains of the cleavage cocktail. The SEC linker is excellently stable to both Lewis and protic acidic conditions combined with a moderate base stability thus allowing the use of amines as reactants or bases in subsequent reactions. Cleavage of SEC linker bound amines was easily effected by treatment of the resins with a cocktail of 1 M NaOMe in THF–MeOH (2 ∶ 1). The widest synthetic scope was found with the TEC linker which combined a sufficient stability against the cationic conditions required for N-acyliminium ion chemistry with complete stability under basic conditions. Cleavage of TEC linker bound amines could be effected by treatment with strong acid or by oxidation of the sulfide to the sulfone (to give the SEC linker) followed by addition of the basic cleavage cocktail.
我们评价了烯丙基、2-磺基乙基(SEC)和2-硫乙基(TEC)氨基甲酸酯连接体系在固载n -酰基离子化学中的应用。作为模型反应，均烯丙基胺(通过从固定氨基甲酸酯开始的三组分方案)和2-取代吡咯烷(通过氨基甲酸酯结合4,4-二氧基-2-苯基丁胺)的合成进行。以低廉的原料制备了所需的前驱体对硝基苯基碳酸酯树脂。在要求的阳离子反应条件下，所有的连接剂都是稳定的。氨基甲酸烯丙酯连接剂的一个严重缺点是繁琐的工作程序，需要去除裂解鸡尾酒的残留物。SEC连接剂在路易斯酸和质子酸条件下都非常稳定，并且具有中等的碱稳定性，因此可以在随后的反应中使用胺作为反应物或碱。用1 M NaOMe在THF-MeOH(2∶1)中混合处理后，可使SEC连接剂结合的胺类化合物裂解。TEC连接剂的合成范围最广，它在n -乙酰基离子化学所需的阳离子条件下具有足够的稳定性，在碱性条件下具有完全的稳定性。用强酸处理或将硫化物氧化为砜(得到SEC连接剂)，然后加入碱性裂解鸡尾酒，可以影响TEC连接剂结合胺的裂解。
{"title":"Development and application of allyl, 2-sulfonylethyl and 2-thioethyl carbamate linkers for solid phase N-acyliminium ion chemistry.","authors":"J. Maarseveen, Wim J. N. Meester, J. Veerman, C. G. Kruse, P. Hermkens, F. Rutjes, H. Hiemstra","doi":"10.1039/B100998M","DOIUrl":"https://doi.org/10.1039/B100998M","url":null,"abstract":"We have evaluated the allyl, 2-sulfonylethyl (SEC) and 2-thioethyl (TEC) carbamate linker systems for their application in solid supported N-acyliminium ion chemistry. As model reactions the syntheses of both homoallylic amines (via a three component protocol starting from an immobilised primary carbamate) and 2-substituted pyrrolidines (via carbamate bound 4,4-diethoxy-2-phenylbutylamine) were conducted. The required precursor p-nitrophenyl carbonate resins were prepared in high yields from cheap starting materials. All linkers proved to be stable under the required cationic reaction conditions. A serious drawback of the allyl carbamate linker is the tedious work up procedure which is required for the removal of the remains of the cleavage cocktail. The SEC linker is excellently stable to both Lewis and protic acidic conditions combined with a moderate base stability thus allowing the use of amines as reactants or bases in subsequent reactions. Cleavage of SEC linker bound amines was easily effected by treatment of the resins with a cocktail of 1 M NaOMe in THF–MeOH (2 ∶ 1). The widest synthetic scope was found with the TEC linker which combined a sufficient stability against the cationic conditions required for N-acyliminium ion chemistry with complete stability under basic conditions. Cleavage of TEC linker bound amines could be effected by treatment with strong acid or by oxidation of the sulfide to the sulfone (to give the SEC linker) followed by addition of the basic cleavage cocktail.","PeriodicalId":17266,"journal":{"name":"Journal of The Chemical Society (resumed)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75199541","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 signs and magnitudes of nuclear overhauser effects observed in closed-shell ion pairs in C2HCl3 show an unusual temperature dependence; freezing point depression measurements support the proposal that the observed dependence is due at least in part to the formation of ion aggregates.
{"title":"The Sign of the Nuclear Overhauser Effect as a Function of Temperature in Contact Ion Pairs","authors":"T. Pochapsky, P. M. Stone, E. Callagari","doi":"10.1039/C39920000178","DOIUrl":"https://doi.org/10.1039/C39920000178","url":null,"abstract":"The signs and magnitudes of nuclear overhauser effects observed in closed-shell ion pairs in C2HCl3 show an unusual temperature dependence; freezing point depression measurements support the proposal that the observed dependence is due at least in part to the formation of ion aggregates.","PeriodicalId":17266,"journal":{"name":"Journal of The Chemical Society (resumed)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1992-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73884556","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}
Rigorous relations between the moments 〈plxpmypnz〉 and 〈pn〉 and the characteristic function B(r) of the momentum density distribution ρ(p) are here generalized to the case of negative l, m, and n. A simple application is given which illustrates that the present results enable us to obtain the moments of momenta without referring to any momentum‐space quantity.
{"title":"Characteristic function of momentum density distribution. II","authors":"T. Koga","doi":"10.1063/1.445896","DOIUrl":"https://doi.org/10.1063/1.445896","url":null,"abstract":"Rigorous relations between the moments 〈plxpmypnz〉 and 〈pn〉 and the characteristic function B(r) of the momentum density distribution ρ(p) are here generalized to the case of negative l, m, and n. A simple application is given which illustrates that the present results enable us to obtain the moments of momenta without referring to any momentum‐space quantity.","PeriodicalId":17266,"journal":{"name":"Journal of The Chemical Society (resumed)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1982-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85848221","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}
R. Kind, S. P. ko, H. Arend, R. Blinc, B. ek, J. Seliger, B. L. ar, J. Slak, A. Levstik, C. Filipi, V. agar, G. Lahajnar, F. Milia, G. Chapuis
The two structural phase transitions in the perovskite layer structure compound (C10H21NH3)2CdCl4 at Tc1=35 °C and Tc2=39 °C have been studied by x‐ray diffractional, calorimetric and dielectric measurements, proton NMR spin–lattice relaxation and second moment investigations, 35Cl and 14N quadrupole resonance spectroscopy as well as group theoretical considerations. The results show that the transition (Tc1) from the low temperature phase (P21/n) to the intermediate temperature phase (Pmnn) is basically a dynamic order–disorder transition of rigid alkyl chains, whereas the transition (Tc2) from the intermediate to the high temperature phase (Amaa) is connected with a melting of the alkyl chains. In the intermediate phase the rigid alkyl chains are flipping around their long axes between two equivalent orientations separated by 90°. The two transitions are somewhat analogous to the ones found in the lipid bilayer membranes and can be described by order parameters used for smectic liquid crystals.
{"title":"Dynamics of the n-decylammonium chains in the perowskite-type Layer structure compound (C10H21NH3)2CdCl4","authors":"R. Kind, S. P. ko, H. Arend, R. Blinc, B. ek, J. Seliger, B. L. ar, J. Slak, A. Levstik, C. Filipi, V. agar, G. Lahajnar, F. Milia, G. Chapuis","doi":"10.1063/1.438584","DOIUrl":"https://doi.org/10.1063/1.438584","url":null,"abstract":"The two structural phase transitions in the perovskite layer structure compound (C10H21NH3)2CdCl4 at Tc1=35 °C and Tc2=39 °C have been studied by x‐ray diffractional, calorimetric and dielectric measurements, proton NMR spin–lattice relaxation and second moment investigations, 35Cl and 14N quadrupole resonance spectroscopy as well as group theoretical considerations. The results show that the transition (Tc1) from the low temperature phase (P21/n) to the intermediate temperature phase (Pmnn) is basically a dynamic order–disorder transition of rigid alkyl chains, whereas the transition (Tc2) from the intermediate to the high temperature phase (Amaa) is connected with a melting of the alkyl chains. In the intermediate phase the rigid alkyl chains are flipping around their long axes between two equivalent orientations separated by 90°. The two transitions are somewhat analogous to the ones found in the lipid bilayer membranes and can be described by order parameters used for smectic liquid crystals.","PeriodicalId":17266,"journal":{"name":"Journal of The Chemical Society (resumed)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1979-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81313887","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}
Incubation of squalene 2,3;22,23-diepoxide with microsomes of Rubus fruticosa gives 24,25-epoxycycloartanol.
角鲨烯2,3;22,23-二氧化二氮化物与猕猴桃微粒体孵育得到24,25-环氧环artanol。
{"title":"Cyclisation of squalene 2,3;22,23-diepoxide by microsomes from bramble (Rabus fruticosa) tissues grown in vitro","authors":"R. Heintz, P. Benveniste","doi":"10.1039/C29700000946","DOIUrl":"https://doi.org/10.1039/C29700000946","url":null,"abstract":"Incubation of squalene 2,3;22,23-diepoxide with microsomes of Rubus fruticosa gives 24,25-epoxycycloartanol.","PeriodicalId":17266,"journal":{"name":"Journal of The Chemical Society (resumed)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1970-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83358249","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}
{"title":"481. Radiation chemistry of carbohydrates. Part XV. Mechanism of self-decomposition of [C]D-glucose","authors":"G. Phillips, K. Davies","doi":"10.1039/JR9650002654","DOIUrl":"https://doi.org/10.1039/JR9650002654","url":null,"abstract":"","PeriodicalId":17266,"journal":{"name":"Journal of The Chemical Society (resumed)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1965-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78489060","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}
{"title":"1105. Electrophilic additions to alkenes. Part I. Kinetics of the reaction of 2,4-dinitrobenzenesulphenyl bromide with cyclohexene in acetic acid solution","authors":"D. Campbell, D. Hogg","doi":"10.1039/JR9650005887","DOIUrl":"https://doi.org/10.1039/JR9650005887","url":null,"abstract":"","PeriodicalId":17266,"journal":{"name":"Journal of The Chemical Society (resumed)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1965-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73516342","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}
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