Reagent-controlled asymmetric homologation of boronic esters by enantioenriched main-group chiral carbenoids.
نویسندگان
چکیده
[reaction: see text] Putative enantioenriched carbenoid species, (R)-1-chloro-2-phenylethylmagnesium chloride (9) and (S)-1-chloro-2-phenylethyllithium (26), generated in situ by sulfoxide ligand exchange from (-)-(R(S),R)-1-chloro-2-phenylethyl p-tolyl sulfoxide (8), effected the stereocontrolled homologation of boronic esters. sec-Alcohols derived from the product boronates by oxidation with basic hydrogen peroxide exhibited % ee closely approaching that of sulfoxide 8 in examples employing Li-carbenoid 26.
منابع مشابه
Enantioselective synthesis of α-phenyl- and α-(dimethylphenylsilyl)alkylboronic esters by ligand mediated stereoinductive reagent-controlled homologation using configurationally labile carbenoids.
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ورودعنوان ژورنال:
- Organic letters
دوره 8 4 شماره
صفحات -
تاریخ انتشار 2006