Preparation of silyl substituted crotylzinc reagents and their highly diastereoselective addition to carbonyl compounds.
نویسندگان
چکیده
Readily prepared beta-silyl substituted crotylzinc reagents undergo highly selective allylation of carbonyl compounds leading to syn-homoallylic alcohols.
منابع مشابه
Selective synthesis of functionalized, tertiary silanes by diastereoselective rearrangement-addition.
[reaction: see text] Treatment of hydroxy-substituted silyl epoxides with Grignard reagents induces a 1,2-carbon shift to reveal alpha-silyl aldehydes, which are trapped by highly diastereoselective addition reactions of the Grignard reagent. The starting epoxides are readily accessible from propargylic alcohols by regio- and diastereoselective hydrosilylation and epoxidation reactions. In addi...
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The current realm of Lewis acid-promoted propargylsilane additions to carbonyl groups2 may be subdivided into two mechanistically distinct categories: (i) additions proceeding via a desilylation pathway;3 (ii) additions involving a [1,2]-silyl shift.4 Process (i) generates allenic alcohols and is most common when nonbulky silyl groups such as TMS are employed,3 whereas the latter scenario has b...
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ورودعنوان ژورنال:
- Chemical communications
دوره 16 شماره
صفحات -
تاریخ انتشار 2008