2-Azabuta-1,3-diene-4-carbonitriles: stereoselective synthesis and nucleophilic substitution at the carbon-nitrogen double bond

Article abstract of DOI:10.1139/v96-032

The synthesis of (E)-1-methoxy-2-azabuta-1,3-diene-4-carbonitriles was performed by methylation of N-alkenylamides 9 and 11. The Z isomers were obtained by treatment of (E)-1-methylthio-2-azabuta-1,3-diene-4,4-dicarbonitriles with sodium methoxide in methanol. We also describe the reactions of (E)-1-methylthio-2-azabuta-1,3-diene-4,4-dicarbonitriles with pyrrolidine, which afforded 1-(1-pyrrolidinyl) derivatives 20, 21, and 23. X-ray crystallographic analyses of 21 and 23 established the E stereochemistry of the C - N double bond.