4171-83-9Relevant articles and documents
Synthesis of N-allyl and N-acyl-2-vinylindoline
Mazgarova,Gataullin
, p. 672 - 675 (2014)
Heating a mixture of (2R*,3R*)- and (2R*,3S*)-2- [(1S*)-1-iodoethyl]-3,5-dimethyl-1-[(2-nitrophenyl) sulfonyl]indolines with N-isopropylpiperidine in xylene resulted in (2S*,3R*)-3,5- dimethyl-1-[(2-nitrophenyl) sulfonyl]-2-vinylindoline. The latter reacted with thiophenol to afford (2S*,3R*)-3,5-dimethyl-2-vinylindoline, whose reaction with allyl halides or acetyl bromide gave rise to N-allyl-, N-propenyl-, or N-acetyl derivatives. Nitration of 1-acetyl-3,5-dimethyl-2- vinylindoline yielded ortho-nitro derivative.
Synthesis of thioethers, arenes and arylated benzoxazoles by transformation of the C(aryl)-C bond of aryl alcohols
Chen, Bingfeng,Han, Buxing,Liu, Mingyang,Meng, Qinglei,Song, Jinliang,Zhang, Pei,Zhang, Zhanrong
, p. 7634 - 7640 (2020/08/14)
Transformation of aryl alcohols into high-value functionalized aromatic compounds by selective cleavage and functionalization of the C(aryl)-C(OH) bond is of crucial importance, but very challenging by far. Herein, for the first time, we report a novel and versatile strategy for activation and functionalization of C(aryl)-C(OH) bonds by the cooperation of oxygenation and decarboxylative functionalization. A diverse range of aryl alcohol substrates were employed as arylation reagents via the cleavage of C(aryl)-C(OH) bonds and effectively converted into corresponding thioether, arene, and arylated benzoxazole products in excellent yields, in a Cu based catalytic system using O2 as the oxidant. This study offers a new way for aryl alcohol conversion and potentially offers a new opportunity to produce high-value functionalized aromatics from renewable feedstocks such as lignin which features abundant C(aryl)-C(OH) bonds in its linkages.
Intermediacy of Copper(I) under Oxidative Conditions in the Aerobic Copper-Catalyzed Decarboxylative Thiolation of Benzoic Acids
Green, Kerry-Ann,Hoover, Jessica M.
, p. 1769 - 1782 (2020/02/06)
An experimental mechanistic study of the aerobic copper-catalyzed decarboxylative thiolation of benzoic acids with arenethiols is reported. For the model reaction, the findings support the corresponding disulfide (PhSSPh) of the arenethiol (PhSH) as the active thiolating source under reaction conditions. Synthesis and reactivity studies along with kinetic measurements support the chemical and kinetic competence of catalytically active well-defined Cu complexes: (phen)CuI(O2CC6H4-o-NO2) (2), [(phen)CuI(μ-SC6H5)]2 (3), (phen)CuI(C6H4-o-NO2) (4), and (phen)CuII(O2CC6H4-o-NO2)2 (5) (phen = 1,10-phenanthroline). The presence of an induction period in the stoichiometric reaction of the copper(II) complex (phen)CuII(O2CC6H4-o-NO2)2 (5) with PhSSPh and the absence of an induction period in the analogous stoichiometric reaction of the copper(I) complex (phen)CuI(O2CC6H4-o-NO2) (2) suggest that a copper(I) carboxylate is a more likely intermediate than a copper(II) carboxylate. The observation of in situ reduction of CuII to CuI further supports CuI as the primary active catalytic species, and spectroscopic studies also indicate the catalyst resting state to be a CuI species. The catalytic reaction exhibits a first-order dependence on [CuI] and [2-nitrobenzoic acid] and a zero-order dependence on [PhSSPh] and p(O2), suggestive of turnover-limiting decarboxylation of a copper(I) carboxylate. Oxygen was found to promote the essential oxidative cleavage of the copper(I) thiolate intermediate [(phen)CuI(μ-SC6H5)]2 (3) to regenerate a catalytically active [(phen)CuII] (Cuox) species with concomitant formation of PhSSPh. On the basis of these findings, a reaction pathway is proposed for the C-S coupling reaction that includes the key CuI-based intermediates (phen)CuI(O2CC6H4-o-NO2) (2) and (phen)CuI(C6H4-o-NO2) (4). The pathway accounts for the role of O2 in generating the active thiolating source, PhSSPh, as well as enabling catalytic turnover of in situ generated [(phen)CuI(μ-SC6H5)]2 (3).
