Asymmetric synthesis of tertiary and quaternary allyl- and crotylsilanes via the borylation of lithiated carbamates.
نویسندگان
چکیده
Tertiary allyl- or crotylsilanes have been prepared in high er and dr via the lithiation-borylation reaction of alkyl carbamates with silaboronates. Using a related strategy, quaternary allylsilanes could be accessed in similarly high er.
منابع مشابه
Asymmetric synthesis of 1-heteroaryl-1-arylalkyl tertiary alcohols and 1-pyridyl-1-arylethanes by lithiation-borylation methodology.
The synthesis of highly enantioenriched α-heterocyclic tertiary alcohols has been achieved via lithiation-borylation of a configurationally stable lithiated carbamate and heterocyclic pinacol boronic esters followed by oxidation. Protodeboronation of the α-heterocyclic tertiary boronic esters using TBAF·3H2O or CsF gave highly enantioenriched 1-pyridyl-1-arylethanes in high er.
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عنوان ژورنال:
- Organic letters
دوره 13 6 شماره
صفحات -
تاریخ انتشار 2011