Radical Silyl‐ and Germylzincation of Propargylic Alcohols
نویسندگان
چکیده
The silyl- and germylzincation of terminal or internal propargylic alcohols by reaction with (Me3Si)3SiH/Et2Zn, [(Me3Si)3Si]2Zn/Et2Zn Ph3GeH/Et2Zn is examined. These reactions proceed through the addition silicon- germanium-centered radicals across carbon≡carbon triple bond followed trapping diethylzinc produced vinyl radical homolytic substitution at zinc atom. influence hydroxy unit on regio- stereoselectivity these discussed compared to its role played in hydrosilylation hydrogermylation reactions. Protocols developed achieve β-regioselective silylzincation propargyl alcohol α-regioselective are particularly important, as they occur trans stereoselectivity. For both procedures C(sp2)−Zn remains available for subsequent in-situ electrophilic leading overall net alkyne difunctionalization.
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ژورنال
عنوان ژورنال: Helvetica Chimica Acta
سال: 2021
ISSN: ['1522-2675', '0018-019X']
DOI: https://doi.org/10.1002/hlca.202100128