AbstractThis paper presents the results of a study of the alternating copolymerization of alkyl vinyl ethers, as electron‐donors (D), with maleonitrile and fumaronitrile, respectively, as electronacceptors (A), and a13C NMR evaluation of the stereochemistry of the copolymers. The results show that the two copolymers are stereochemically different. By use of model compounds as well as UV studies and quantum chemical (PVCILO) calculations, attempts to correlate the relationship of the complex (C) to copolymer structure have been made. We have previously reported studies on copolymerization of alkyl vinyl ethers andN‐substituted maleimides. Stereochemical consequences resulting from variation of five parameters, each of which according to Mulliken theory should vary the concentration of C relative to that of the free monomers, in every case, were that thecis‐transratio of the succinimide unit of the copolymer chain varied in accord with theory, being higher at highe