A highly efficient alkyl-selective addition to ketones with magnesium ate complexes derivedfromGrignardreagents and alkyllithiums is described. The nucleophilicity of R in R3MgLi is remarkably increased compared to that of the original RLi or RMgX, while the basicity of R3MgLi is decreased. Furthermore, a highly R-selective addition to ketones is demonstrated using RMe2MgLi in place of R3MgLi. [reaction:
Highly efficient alkylations and arylations of ketones with Grignard reagents (RMgBr and RMgI) have been developed using catalytic ZnCl(2), Me(3)SiCH(2)MgCl, and LiCl. Tertiary alcohols were obtained in high yields with high chemoselectivities, while minimizing undesired side products produced by reduction and enolization.
The addition of organometallic reagents to carbonyl compounds has become a versatile method for synthesizing tertiary and secondary alcohols via carbon−carbon bond formation. However, due to the lack of good nucleophilicity or the presence of strong basicity of organometallic reagents, the efficientsynthesis of tertiary alcohols from ketones has been particularly difficult and, thus, limited. We recently
向羰基化合物中添加有机金属试剂已成为通过碳-碳键形成合成叔醇和仲醇的通用方法。然而,由于缺乏良好的亲核性或存在有机金属试剂的强碱性,由酮有效地合成叔醇特别困难并且因此受到限制。我们最近使用ZnCl 2,Me 3 SiCH 2开发了格氏试剂(RMgX:R =烷基,芳基; X = Cl,Br,I),对酮进行了高效的催化烷基化和芳基化反应MgCl和LiCl,可有效减少有问题的副反应。原则上,对于加成羰基化合物,RMgBr和RMgI的反应性不如RMgCl。因此,这种新颖的方法与均相催化的ZnCl 2 ·我3 SICH 2 MgCl·LiCl是相当有吸引力的,因为RMgBr和RMGI,其易于制备和/或可商购的,如RMgCl,可以成功地应用。除酮和醛以外,醛亚胺也有效地用于该催化反应,并以高收率获得了相应的仲胺。关于β-甲硅烷基效应和盐效应的机理细节,原位制备[R(Me 3 SiCH 2)2 Zn] -
Added-Metal-Free Catalytic Nucleophilic Addition of Grignard Reagents to Ketones
作者:Hua Zong、Huayin Huang、Junfeng Liu、Guangling Bian、Ling Song
DOI:10.1021/jo3004277
日期:2012.5.18
reagents to the side of dimeric Grignardreagents to favor the additions of Grignardreagents to ketones via a favored six-membered transition state to form the desired tertiary alcohols, and DGDE should increase the nucleophilic reactivities of Grignardreagents by coordination. This catalytic system has been applied in the efficient synthesis of Citalopram, an effective U.S. FDA-approved antidepressant
NONSTEROIDAL COMPOUNDS USEFUL AS MODULATORS OF GLUCOCORTICOID RECEPTOR AP-1 AND/OR NF-KAPPAB ACITIVITY AND USE THEREOF
申请人:Dhar T.G. Murali
公开号:US20110263494A1
公开(公告)日:2011-10-27
Disclosed are compounds of Formula (I) wherein: one of A and D is —N— and the other of A and D is —C—; or enantiomers, diastereomers, or pharmaceutically-acceptable salts thereof. Also disclosed are methods of using such compounds to modulate the function of glucocorticoid receptor activity and pharmaceutical compositions comprising such compounds.