Light-induced synthesis of unsymmetrical organic carbonates from alcohols, methanol and CO<sub>2</sub> under ambient conditions
作者:Sandhya Saini、Nand Kishor Gour、Shafiur Rehman Khan、Ramesh Chandra Deka、Suman L Jain
DOI:10.1039/d1cc05833a
日期:——
The present work describes the first visible light-assisted, metal-free and organic base 1,1,3,3-tetramethyl guanidine (TMG) mediated synthesis of unsymmetrical methyl aryl/alkyl carbonates from the reaction of alcohols, methanol, and CO2 in high to excellent yields under atmospheric pressure and ambient temperature conditions.
目前的工作描述了第一个可见光辅助、无金属和有机碱 1,1,3,3-四甲基胍 (TMG) 介导的由醇、甲醇和 CO 2的反应合成的不对称甲基芳基/碳酸烷基酯在大气压和环境温度条件下以高到极好的收率。
Oxidative carbonylation of monohydroxy aryl compounds by methyl formate
申请人:Bayer MaterialScience AG
公开号:EP2781503A1
公开(公告)日:2014-09-24
The field of the present invention relates to a process for continuously preparing alkylaryl carbonates and diarylcarbonates from methyl formate and at least one monohydroxy aryl compound in the presence of catalysts, and to the use thereof for preparation of polycarbonates.
Ketene acetals from thermolysis of aryloxy methoxy oxadiazolines. Evidence for carbonyl ylide intermediates
作者:Philippe Couture、Manal El-Saidi、John Warkentin
DOI:10.1139/v97-037
日期:1997.3.1
sequence of thermolysis of oxadiazolines, namely, initial cycloreversion to N2 and carbonylylide (6), rather than concerted fragmentation to N2, acetone, and carbene (12). The first-formed ylide does fragment to carbene and acetone in a second step that competes with oxirane formation. A tentative mechanism for reaction of 7 with 12, to afford 11, is advanced. Keywords: carbonylylide, dioxy oxirane
The potential catalytic activity of selected C,N‐chelated organotin(IV) compounds (e.g. halides and trifluoroacetates) for derivatization of both dimethyl carbonate (DMC) and diethyl carbonate (DEC) was investigated. Some tri‐, di‐ and monoorganotin(IV) species (LCN(n‐Bu)2SnCl (1), LCN(n‐Bu)2SnCl.HCl (1a), LCN(n‐Bu)2SnI (2), LCNPh2SnCl (3), LCNPh2SnI (4), LCN(n‐Bu)SnCl2 (5), LCNSnBr3 (6) and [LCNS
character (aliphatic and aromaticamines, alcohoxydes, phenoxides, thiolates) are compared with regard to nucleophilic substitutions on dimethyl carbonate (DMC), using different reaction conditions. Results are well in agreement with the Hard−Soft Acid−Base (HSAB) theory. Accordingly, the high selectivity of monomethylation of CH2 acidic compounds and primaryaromaticamines with DMC can be explained