A practical and useful, catalyticenantioselective method has been developed for the synthesis of tertiary diaryl and aryl heteroaryl carbinols starting from commercially available aromatic ketones and aryl or heteroaryl bromides. In this method, organotitanium reagents are generated in situ from the bromides by lithiation with nBuLi followed by transmetallation of the resulting organolithiums with
已经开发了一种实用且有用的催化对映选择性方法,用于从可商购的芳族酮和芳基或杂芳基溴化物开始合成叔二芳基和芳基杂芳基甲醇。在该方法中,通过用n BuLi锂化从溴化物中原位生成有机钛试剂,然后用ClTi(O i Pr)3对所得的有机锂进行金属转移。在(R)-3-(3,5-双三氟甲基苯基)-1,1'-联-2-萘酚(BTFP-BINOL)以高对映选择性和高收率提供了相应的叔醇。反应也可以从呋喃和2-噻吩基锂开始。该方法操作简单,可在10 mmol规模下进行而没有任何困难。
Asymmetric Direct 1,2-Addition of Aryl Grignard Reagents to Aryl Alkyl Ketones
作者:Kazuki Osakama、Makoto Nakajima
DOI:10.1021/acs.orglett.5b03379
日期:2016.1.15
The enantioselective addition of Grignardreagents to ketones was promoted by a BINOL derivative bearing alkyl chains at the 3,3′-positions. This is the first asymmetric direct aryl Grignard addition to ketones reported to date. A variety of tertiary diaryl alcohols could be obtained in high yields and enantioselectivities without using any other metal source.
MgBr<sub>2</sub>-promoted enantioselective aryl addition of ArTi(O<sup>i</sup>Pr)<sub>3</sub> to ketones catalyzed by a titanium(<scp>iv</scp>) catalyst of N,N′-sulfonylated (1R,2R)-cyclohexane-1,2-diamine
作者:Chao-Chi Shu、Shuangliu Zhou、Han-Mou Gau
DOI:10.1039/c5ra18871g
日期:——
MgBr2-promoted asymmetric addition of ArTi(OiPr)3 to ketonescatalyzed by a titanium catalyst of N,N′-sulfonylated (1R,2R)-cyclohexane-1,2-diamines is reported, and results showed that the chiral N,N′-sulfonylated cyclohexane-1,2-diamines with electron-withdrawing groups could effectively catalyze asymmetric addition of ArTi(OiPr)3 to ketones to afford desired tertiary alcohols in good yields with
据报道,MgBr 2促进了N,N'-磺酰化(1 R,2 R)-环己烷-1,2-二胺的钛催化剂催化的酮类化合物向酮中不对称地添加ArTi(O i Pr)3,结果表明:具有吸电子基团的手性N,N'-磺酰化环己烷-1,2-二胺可以有效催化不对称地将ArTi(O i Pr)3加到酮上,以高收率提供所需的叔醇,并具有良好的对映选择性。到95%ee。