Isopropyl N -Arylmalonamates. Synthesis, Structure, Conformation and Reactions with Carbon Disulfide

Acylation of aromatic amines 1 with diisopropyl malonate ( 2 ) leads to a mixture of isopropyl N -arylmalonamates 3 and malonanilides 4 . The reaction of 3 with carbon disulfide in the presence of sodium hydride gives disodium salts 5 . Treatment of 5 with an alkylating agent yields the open-chain or cyclic ketene dithioacetals 6 , 7 or 8 . The molecular structure, hydrogen bonding and preferential conformation of the isopropyl N -arylmalonamates 3 , 6 and 7 were investigated using correlation analyses of IR, 13 C NMR and AM1 semiempirical data.