19289-28-2Relevant articles and documents
Alkylation of active methylenes via benzhydryl cations
Bisaro, Fabrice,Prestat, Guillaume,Vitale, Maxime,Poli, Giovanni
, p. 1823 - 1826 (2002)
The acid mediated reaction between active methylenes and benzhydryl alcohols, or their derivatives, is reported. Ethyl acetoacetate, acetylacetone, and N,N-dibenzyl-malonamic acid methyl ester are benzhydrylated in quantitative yields in the presence of molar amounts of BF3·OEt2 in CH2Cl2 at r.t. TMSOTf and H2SO4 appear to be equally efficient. Use of benzhydryl acetate in place of the starting free alcohol allows lowering of the Lewis acid to catalytic amounts. A general mechanism for this scarcely studied C-C bond formation is presented. Due to the easier availability of alcohols with respect to halides the method may favorably compare with the more classical halide-based basic conditions.
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Henderson,Parker
, p. 676 (1897)
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Air-stable μ2-hydroxyl bridged cationic binuclear complexes of zirconocene perfluorooctanesulfonates: their structures, characterization and application
Zhang, Xiaohong,Xu, Xinhua,Li, Ningbo,Liang, Zhiwu,Tang, Zilong
supporting information, p. 1926 - 1932 (2018/03/21)
Three air-stable zirconocene perfluoro-octanesulfonates were successfully synthesized by treatment of C8F17SO3Ag with (RCp)2ZrCl2 [R = H, n-Bu, t-Bu]. According to X-ray analysis, they have μ2-hydroxyl bridged cationic binuclear structures: (i) [CpZr(OH2)3]2(μ2-OH)2(OSO2C8F17)4·2THF·4H2O (1a·2THF·4H2O), (ii) [n-BuCpZr(OH2)3]2(μ2-OH)2(OSO2C8F17)4·6H2O (2a·6H2O), and (iii) [t-BuCpZr(OH2)3]2(μ2-OH)2(OSO2C8F17)4·2C3H6O·8H2O (3a·2C3H6O·8H2O). The ligands of water and organic molecules in the complexes originated from the moist air and solvent during their recrystallization. These complexes were characterized with different techniques, and found to show water tolerance, air/thermal stability as well as strong Lewis acidity. Moreover, the complexes showed highly catalytic activity in various reactions of C–C bond formation. With good recyclability, they should find wide applications in organic chemistry.
Protecting group-free use of alcohols as carbon electrophiles in atom efficient aluminium triflate-catalysed dehydrative nucleophilic displacement reactions
Cullen, Adam,Muller, Alfred J.,Williams, D. Bradley G.
, p. 42168 - 42171 (2017/09/11)
Benzylic and allylic alcohols are rendered electrophilic without chemical modification by the use of aluminium triflate as catalyst. The reaction succeeds with alcohol, thiol, carbon and nitrogen nucleophiles. When phenols are employed as nucleophiles, C-alkylation ensues. An advanced application of the method is demonstrated in the synthesis of 2H-chromenes and their N and S analogues.
