Conjugate addition of 2- and 4-pyridylcuprates: an expeditious asymmetric synthesis of natural (-)-evoninic acid.
نویسندگان
چکیده
[reaction: see text] The scope and limitations of the conjugate addition of 2- and the first 4-pyridyl Gilman homocuprates to various alpha,beta-unsaturated Michael acceptors are delineated. The conjugate addition of the cuprate of 2-bromo-3-methylpyridine to (E)-methyl crotonate then diastereoselective enolate alkylation and lipase-mediated enantioselective ester hydrolysis have enabled an efficient four-step first asymmetric synthesis of the Celastraceae sesquiterpenoid esterifying ligand (-)-(1'S,2'S)-evoninic acid.
منابع مشابه
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ورودعنوان ژورنال:
- Organic letters
دوره 9 5 شماره
صفحات -
تاریخ انتشار 2007