The Alkylation of Ethyl 3-Oxoglutarate

Abstract

The selective alkylation of ethyl 3-oxoglutarate was achieved through its Mg-complex prepared from a normal coordinate treatment with Mg (OEt)₂. The structural elucidation of this complex was substantiated by comparison of Cu and Mg chelate compounds prepared from acetylacetone and ethyl acetoacetate.
Mg-complex of ethyl 3-oxoglutarate reacted with alkyl halides (RX) in the presence of Mg (OEt)₂ or NaOEt as basic catalyst, followed by hydrolysis with hydrochloric acid to give ethyl 2-R-3-oxoglutarate (yield, 78_??_80%). Moreover, the synthesis of ethyl 2-R-4-R'-3-oxoglutarate from ethyl 2-R-3-oxoglutarate can be conducted successfully by using alkyl halides (R'X) in the presence of NaOEt as catalyst (yield, 81_??_82%).