Novel reactions of indium reagents with 1,2-diones: a facile synthesis of α-hydroxy ketones
作者:Vijay Nair、C.N Jayan、Sindu Ros
DOI:10.1016/s0040-4020(01)00937-1
日期:2001.11
Indium mediated reactions of allyl, cinnamyl, propargyl and benzyl bromides, ethyl bromoacetate and ethyl-4-bromocrotonate with 1,2-diones, in the presence of sodium iodide, occur efficiently to afford α-hydroxy keto compounds in excellent yields.
A new method for conducting a reductive alkylation/arylation of 1,2-diketones using visible light and unactivated organic halides is presented in this article. This technique does not require a photocatalyst and employs Et3N, a tertiary amine, as a promoter. This amine aids in generating a ketyl radical and an α-aminoalkyl radical, which engages in a C–X bond activation via a halogen atom transfer
本文介绍了一种使用可见光和未活化的有机卤化物对 1,2-二酮进行还原烷基化/芳基化的新方法。该技术不需要光催化剂,并使用叔胺Et 3 N 作为促进剂。这种胺有助于生成一个羰基自由基和一个 α-氨基烷基自由基,后者通过卤素原子转移过程 (XAT) 参与 C-X 键活化。这种方法的成功取决于利用 Et 3 N 作为启动子。本文温和直接的协议允许显着扩展有机卤化物底物,包括主要、次要和芳香族有机卤化物和各种官能团。
Photo-allylation and photo-benzylation of carbonyl compounds using organotrifluoroborate reagents
作者:Yutaka Nishigaichi、Takayuki Orimi、Akio Takuwa
DOI:10.1016/j.jorganchem.2009.08.011
日期:2009.11
Allyl- and benzyl-trifluoroborates can be applied to the photoreaction of carbonylcompounds to afford the corresponding alcoholic adducts in acceptable yields via a photo-induced single electron transfer pathway. The results were confirmed from the reaction selectivity and the negative free energy change for the electron transfer process.
reaction is not a simple substitution of the hydroxy group with amines, but goes through imine formation followed by 1,2-C migration. The reaction provides good opportunity for the synthesis of opticallyactive α-amino ketones. We have achieved facile synthesis of some chromatographically separable and opticallyactive tert-α-amino ketones by employing S-(−) or R-(+)-α-methylbenzylamines in the Voight