Synthesis of acylketene N,N-acetals and their E,Z-isomerism

A method was proposed for the synthesis of acylketene N,N-acetals (AKA) by the action of methanol in the presence of Co²⁺ acetate on diacylketene N,N-acetals. Using¹H and¹³C NMR spectroscopy, a restrainment of the internal rotation around the C=C bond of AKA was discovered, and the influence of solvation of the dynamic equilibrium of the E- and Z-isomers was studied.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 401–407, February, 1990.