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Please login or sign up for a free trial to access the full content. Variation 5: Alkenation of α-Oxo Esters

DOI: 10.1055/sos-SD-020-01227

Vanderwal, C. D.; Jacobsen, E. N.Science of Synthesis, (2007201325.

The alkenation of α-oxo esters is a very general method for the introduction of the alk-2-enoic acid ester function. The alkene synthesis can make use of many different methods, including aldol condensation, Wittig and HornerWadsworthEmmons reactions. The condensation of methyl glyoxalate with pyranone 115 proceeds in good yield to produce alk-2-enoic acid ester 116 as the single geometrical isomer (Scheme 21).[‌73‌] An intramolecular variant of this aldol condensation reactivity enables the synthesis of alk-2-enoic acid ester 118 from methyl ketone/α-oxo ester 117 in high yield.[‌74‌]

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