Ligand-Controlled Chemoselective C(acyl)–O Bond vs C(aryl)–C Bond Activation of Aromatic Esters in Nickel Catalyzed C(sp<sup>2</sup>)–C(sp<sup>3</sup>) Cross-Couplings
converted into the alkylated arenes and ketone products, respectively. The utility of this newly developed protocol was demonstrated by its wide substrate scope, broad functional group tolerance and application in the synthesis of keyintermediates for the synthesis of bioactive compounds. DFT studies on the oxidative addition step helped rationalizing this intriguing reaction chemoselectivity: whereas
Asymmetric Alkyl−Alkyl Cross-Couplings of Unactivated Secondary Alkyl Electrophiles: Stereoconvergent Suzuki Reactions of Racemic Acylated Halohydrins
作者:Nathan A. Owston、Gregory C. Fu
DOI:10.1021/ja105924f
日期:2010.9.1
A method for asymmetric alkyl-alkylSuzuki reactions of unactivatedsecondaryalkyl electrophiles, specifically, cross-couplings of racemic acylated halohydrins with alkylborane reagents, has been developed. A range of protected bromohydrins, as well as a protected chlorohydrin and a homologated bromohydrin, are coupled in good ee by a catalyst derived from commercially available components.
已开发出一种用于未活化仲烷基亲电试剂的不对称烷基-烷基 Suzuki 反应的方法,特别是外消旋酰化卤代醇与烷基硼烷试剂的交叉偶联。一系列受保护的溴醇,以及受保护的氯醇和同系溴醇,通过衍生自市售组分的催化剂以良好的 ee 偶联。
Nickel-Catalyzed Alkoxy-Alkyl Interconversion with Alkylborane Reagents through C−O Bond Activation of Aryl and Enol Ethers
A nickel‐catalyzed alkylation of polycyclic aromatic methyl ethers as well as methyl enol ethers with B‐alkyl 9‐BBN and trialkylborane reagents that involves the cleavage of stable C(sp2)−OMe bonds is described. The transformation has a wide substrate scope and good chemoselectivity profile while proceeding under mild reaction conditions; it provides a versatile way to form C(sp2)−C(sp3) bonds that
A copper(I)‐catalyzed addition of alkylborane reagents to α‐iminoacetates has been developed to assemble both acyclic and cyclic α‐branched α‐amino carboxylic acid derivatives in good yields. A wide variety of unactivated alkenes are well tolerated in this transformation.
Synthesis of Tertiary Alkyl Amines from Terminal Alkenes: Copper-Catalyzed Amination of Alkyl Boranes
作者:Richard P. Rucker、Aaron M. Whittaker、Hester Dang、Gojko Lalic
DOI:10.1021/ja3023829
日期:2012.4.18
one-pot procedure involves hydroboration of the alkene followed by a novel electrophilic amination of the alkyl borane catalyzed by an NHC-Cu complex. Terminal alkenes are successfully transformed into tertiary alkylamines in the presence of a variety of functional groups in yields ranging from 80 to 97% with excellent regioselectivity. Results of a preliminary study of the reaction mechanism are also