NOVEL ASYMMETRIC ALKYLATION OF CYCLIC β-KETO ESTERS WITH OPTICALLY ACTIVE SULFONIUM SALTS
نویسندگان
چکیده
منابع مشابه
Asymmetric allylic alkylation of Morita–Baylis–Hillman carbonates with α-fluoro-β-keto esters
In the presence of a commercially available Cinchona alkaloid as catalyst, the asymmetric allylic alkylation of Morita-Baylis-Hillman carbonates, with α-fluoro-β-keto esters as nucleophiles, have been successfully developed. A series of important fluorinated adducts, with chiral quaternary carbon centres containing a fluorine atom, was achieved in good yields (up to 93%), with good to excellent...
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The highly stereoselective allylic alkylation of Morita-Baylis-Hillman carbonates with β-ketoesters catalysed by β-ICD is described. The corresponding products containing two adjacent quaternary and tertiary carbon centers were obtained in good yields with high diastereoselectivity (up to 10 : 1 dr) and enantioselectivity (up to 95% ee).
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ژورنال
عنوان ژورنال: Chemistry Letters
سال: 1985
ISSN: 0366-7022,1348-0715
DOI: 10.1246/cl.1985.1067