An Efficient Directed Claisen Reaction Allows for Rapid Construction of 5,6-Disubstituted 1,3-Dioxin-4-ones
نویسندگان
چکیده
An efficient directed Claisen reaction between tert-butyl propionate and phenyl propionate is described. This enables a practical synthesis of 6-ethyl-2,2,5-trimethyl-4H-1,3-dioxin-4-one and thereby (Z)-[(4-ethylidene-2,2,5-trimethyl-4H-1,3-dioxin-6-yl)oxy]trimethylsilane, a key building block in our synthesis of macrolide antibiotics. The three-step route elaborated for the preparation of the latter substance requires no chromatography and is amenable to large-scale synthesis.
منابع مشابه
Studies of the Reaction of Various 1,2-Disubstituted Benzenes with Crotonic Acid in Polyphosphoric Acid
H a m i s h G . G r a n t * Department o f Organic Chemistry, University o f Adelaide G . P . O . B o x 498, South Australia 5001 Z. Naturforsch. 34b , 728-733 (1979); received N o v e m b e r 27, 1978 5,6-Disubstituted Indanl -ones , Crotonic Ac id , Po lyphosphor i c Ac id , 1-Methyl Benzofurocyc lopentan-3-one, 1 3C N M R The reaction of several 1,2-disubstituted benzenes with crotonic acid ...
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