机理研究表明,通过双重光氧化还原和钯催化,氨基酯的脱羧烯丙基化通过氧化产生 π-烯丙基-Pd( II ) 物种和羧酸盐发生,后者被 *Ir( III )- 催化剂氧化,提供苄基自由基。烷基化产物是通过S N 2 途径形成的。Pd( I ) 物种和 Ir( II ) 催化之间的单电子转移可恢复这两种催化剂。
Decarboxylative Allylation of Amino Alkanoic Acids and Esters via Dual Catalysis
作者:Simon B. Lang、Kathryn M. O’Nele、Jon A. Tunge
DOI:10.1021/ja508317j
日期:2014.10.1
temperature decarboxylative allylation of recalcitrant α-amino and phenylacetic allyl esters. This operationally simple process produces CO2 as the only byproduct and provides direct access to allylated alkanes. After photochemical oxidation, the carboxylate undergoes radical decarboxylation to site-specifically generate radical intermediates which undergo allylation. A radical dual catalysis mechanism
光氧化还原和钯催化的组合已被用于促进顽固的 α-氨基和苯乙酸烯丙酯的室温脱羧烯丙基化。这个操作简单的过程产生 CO2 作为唯一的副产品,并提供直接获取烯丙基化烷烃的途径。光化学氧化后,羧酸盐发生自由基脱羧作用,以位点特异性地生成自由基中间体,然后进行烯丙基化。提出了一种自由基双催化机制。游离苯乙酸也使用类似的反应条件进行烯丙基化。
Radical Addition-Triggered Remote Migratory Isomerization of Unactivated Alkenes to Difluoromethylene-Containing Alkenes Enabled by Bimetallic Catalysis
A fascinating alkeneremote migratory isomerization engendered by carbon radical addition to C═C bond in alkenes via bimetalliccatalysis has been disclosed. A diverse array of alkenes bearing distantly incorporated the difluoromethylene (RCF2R′) functionality have been expediently obtained. The retainment of C═C bonds in products could serve as an useful synthetic platform furnishing otherwise difficult
Here, we have described a new copper-catalyzed 1,2-dicarbonylative cyclization of 4-aryl-1-butenes with unactivated alkylbromides. In this reaction, two carbonyl groups were introduced into the double bond by the insertion of two molecules of carbon monoxide, and four new C−C bonds could be constructed in one reaction. At the same time, the corresponding skeletons of α-tetralones as well as 2,3-d
Copper-catalyzed borocarbonylation of terminal alkenes usually gives terminal boron substituted β-boryl carbonyl compounds. In this communication, a copper-catalyzed selectivity-reversed borocarbonylation has been described. In the presence of CuOAc/BuPAd2 catalytic system, a series of unactivated terminal alkenes were transformed into β-boryl ketones in moderate yields, with sterically hindered alkyl
Carbonylative multifunctionalization of alkenes is an efficient approach to introduce multiple functional groups into one molecule from easily available materials. Herein, we developed an iron-catalyzed radical relay carbonylativecyclization of alkenes with acetamides. Various α-tetralones can be constructed in moderate yields from readily available substrates with an earth-abundant iron salt as the