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Evidence for single electron transfer in claisen condensation. The reaction of ethyl p-nitrobenzoate with the lithium enolate of pinacolone

โœ Scribed by E.C. Ashby; Won-Suh Park

Publisher
Elsevier Science
Year
1983
Tongue
French
Weight
194 KB
Volume
24
Category
Article
ISSN
0040-4039

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โœฆ Synopsis

The paramagnetic intermediate in the reaction of ethyl p-nitrobenzoate with the lithium enolate of pinacolone is shown to be on the reaction pathway for the formation of the condensation product, 4,4-dimethyl-1-(4-nitrophenyl)-1,3-pentanedione. Claisen condensation is considered one of the most fundamental reactions in synthetic organic chemistry.' It involves the reaction of an ester containing an a-hydrogen with a strong base (e.g., sodium ethoxide), to form a 8-keto ester. The mechanism of this reaction is considered to be well established' and is represented by Scheme I., Scheme I R-CH2-COOR' + OEt-c R-CH-COOR' + EtOH R-CH-COOR'

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