22913-11-7Relevant articles and documents
Metal-free radical aromatic carbonylations mediated by weak bases
Koziakov, Denis,Jacobi Von Wangelin, Axel
supporting information, p. 6715 - 6719 (2017/08/22)
We report a new method of metal-free alkoxycarbonylation. This reaction involves the generation of aryl radicals from arenediazonium salts by a very weak base (HCO2Na) under mild conditions. Subsequent radical trapping with carbon monoxide and alcohols gives alkyl benzoates. The conditions (metal-free, 1 equiv. base, MeCN, r.t., 3 h) tolerate various functional groups (I, Br, Cl, CF3, SF5, NO2, ester). Mechanistic studies indicate the operation of a radical aromatic substitution mechanism.
Dimethylbut-2-ynedioate mediated esterification of acids via sp3 C-N bond cleavage of benzylic tertiary amines
Shen, Hao,Lu, Xing,Jiang, Ke-Zhi,Yang, Ke-Fang,Lu, Yixin,Zheng, Zhan-Jiang,Lai, Guo-Qiao,Xu, Li-Wen
, p. 8916 - 8923 (2012/10/29)
A straightforward synthetic transformation of tertiary amines to the esterification of equimolar amounts of acids was demonstrated in this manuscript. The present protocol can be regarded as a straightforward synthetic transformation of tertiary amines to the esterification of equimolar amounts of acid. Moreover, the reaction is fundamentally new chemistry for the sp 3 C-N bond cleavage coupled with esterification. The esterification reaction conditions are very mild and functional group-tolerated, such as hydrosilanes, alcohols, phenol, and amino acids. A mechanism is proposed in which the tertiary amine reacts with dimethyl but-2-ynedioate to form zwitterionic salt, and then the zwitterionic intermediate subsequently accept hydrogen to assist the nucleophilic attack of oxygen atom of carboxyl group at the benzyl group of tertiary amine, while a separate reaction pathway leads to esterification.
Rhenium complex-catalyzed acylative cleavage of ethers with acyl chlorides
Umeda, Rui,Nishimura, Takashi,Kaiba, Kenta,Tanaka, Toshimasa,Takahashi, Yuuki,Nishiyama, Yutaka
experimental part, p. 7217 - 7221 (2011/10/08)
It was found that rhenium complex was an efficient catalyst for the acylative cleavage of C-O bond of ethers with acyl chlorides. When acyclic ethers were allowed to react with acyl chlorides in the presence of a catalytic amount of ReBr(CO)5, acylative cleavage of C-O bond of acyclic ethers smoothly proceeded to give the corresponding esters in moderate to good yields. Similarly, cyclic ethers were acylative cleaved by acyl chlorides to give the corresponding chloro substituted esters in good yields by the use of Re 2O7 catalyst.