Condensation reactions of 1,1-dimorpholinoethene and of 1,1-dipiperidinoethene with carbon acids

1,1-Dimorpholinoethene and 1,1-dipiperidinoethene condense with such compounds as malononitrile, ethyl cyanoacetate, cyanoacetamide, and diethyl malonate to give the corresponding β,β-disubstituted enamine, a molecule of morpholine or piperidine being eliminated in the process. Similar reactions with acetylacetone and ethyl acetoacetate proceed with loss of the acetyl group to give the β-substituted enamine. 1,1-Dipiperidinoethene and nitromethane give the β-nitroenamine. Secondary processes of either hydrolysis or further Michael addition and elimination are noted in condensations of 1,1-dimorpholinoethene or 1,1-dipiperidinoethene with cyanoacetamide under more basic conditions.1,1-Dipiperidinoethene is arylated at the 2-position by 2,4-dinitrochlorobenzene.