Condensation with succinic acid monoesters

The reaction of cycloheptanone with hexamethylphosphoramide gives (325) in low yield condensations of the ketone with 6-amino-2,4,5-triphenyl-resorcinol to give (326) and with the dianion of methyl- or phenyl-succinic acid monoesters to give (327 R = H or Me) are reported. 

Succinic esters condense with aldehydes and ketones in the presence of bases, eg, sodium alkoxide or piperidine, to form monoesters of alkybdenesuccinic acids, eg, condensation of diethyl succinate with acetone yields ethyl 2-isopropyhdenesuccinate (eq. 3). This reaction, known as Stobbe condensation, is specific for succinic esters and substituted succinic esters (98,99). 

Stobbe condensation. Condensation of aldehydes or ketones with diethyl succinate in the presence of a strong base to form monoesters of a-afkyli-dene (or arylidene) succinic acids. 

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