Radical Allylation, Vinylation, Alkynylation, and Phenylation Reactions of α-Halo Carbonyl Compounds with Organoboron, Organogallium, and Organoindium Reagents
reactions of α-halo carbonyl compounds with alkenylindium proceeded via a radical process in the presence of triethylborane. Unactivated alkene moieties and styryl groups were introduced by this method. The carbon-carbon double bond geometry of the alkenylindiums was retained during the alkenylation. Preparation of an alkenylindium via a hydroindation of 1-alkyne and subsequent radical alkenylation established
Taming the Carboxyl Group for Directed Carbometalation-Observations on the Use of Anions, Dianions and Ester Enolates
作者:Sandy Desrat、Philip J. Gray、Matthew R. Penny、William B. Motherwell
DOI:10.1002/chem.201403294
日期:2014.6.23
Carboxylate anions, dianions and esterenolates provide simultaneous protection and activation for directed carbometalation reactions. Advantage can be taken of the bis‐carbanionic character of the intermediate for further controlled CC bond forming reactions.
adjacent carbons. However, when the reaction was carried out under irradiation using a low-pressure Hg lamp, addition/reduction products were obtained in good yield. Hydrogen bromide, formed by H-abstraction of a bromine radical from alkenes, is likely to play a key role in the reductive ATR reaction.
Iridium complex-catalyzed carbonylation of allylic phosphates
作者:Ryo Takeuchi、Yasushi Akiyama
DOI:10.1016/s0022-328x(02)01370-0
日期:2002.5
[Ir(cod)Cl]2 with a ligand such as P(2-furyl)3, PPh2C6F5 or AsPh3 showed high catalytic activity for the carbonylation of allylic phosphates in the presence of alcohols to give the corresponding β,γ-unsaturatedesters. The carbonylation of diethyl (E)-3-phenyl-2-propenyl phosphate in the presence of EtOH under an initial carbon monoxide pressure of 40 kg cm−2 at 100 °C gave ethyl (E)-4-phenyl-3-butenoate
具有配体如P(2-呋喃基)3,PPh 2 C 6 F 5或AsPh 3的[Ir(cod)Cl] 2在醇存在下显示出对烯丙基磷酸羰基化的高催化活性,得到相应的β ,γ-不饱和酯。(E)-3-苯基-2-丙烯基磷酸二乙酯在EtOH存在下于100 kgC的初始一氧化碳压力为40 kg cm -2的羰基化反应得到(E)-4-苯基-3-丁烯酸乙酯收率达90%。否(Z获得)-异构体。不使用胺作为添加剂,反应进行顺利。在EtOH存在下磷酸2-链烯基二乙酯的羰基化反应得到(E)-和(Z)-3-链烯酸乙酯的混合物。起始原料的立体化学通过丢失顺-反插入一氧化碳的进iridiumcarbon键之前中间到π烯丙基铱的异构化。增加烯丙基系统在γ位上的取代基的空间体积,或增加初始一氧化碳压力,将增加对具有与起始原料相同的立体化学的产物的选择性。
Radical Alkenylation of α-Halo Carbonyl Compounds with Alkenylindiums
Alkenylation reaction of alpha-halo carbonyl compounds with alkenylindiums proceeded via a radical process in the presence of triethylborane. Unactivated alkene moieties as well as a styryl group could be introduced by this method. The geometry of the carbon-carbon double bonds of the alkenylindiums was retained. Preparation of an alkenylindium via a hydroinclation of 1-alkyne followed by radical alkenylation established an efficient one-pot strategy.