Synthesis and Polymerization of Optically Active N-α-Methylbenzylcitraconimide

Abstract

Optically active N-α-methylbenzylcitraconimide (MBZCI) was prepared from citraconic anhydride and d-α-methylbenzylamine. The polymerizations of MBZCI were carried out with α,α′-azobisiso-butyronitrile (AIBN) in several solvents and in bulk. The specific rotations of the polymers were between 48.6 and 56.7°. The number-average molecular weights for the polymers were 1 400 to 1 900. MBZCI was copolymerized with styrene (ST) and methyl methacrylate (MMA) with AIBN in tetrahydrofuran at 50°C to obtain optically active copolymers. The monomer reactivity ratios of MBZCI (M₁) with ST (M₂) and MMA (M₂) were determined as r₁ = 0.12, r₂ = 0.24 in the MBZCI-ST; r₁ = 0.23, r₂ = 2.38 in the MBZCI-MMA system. The Q-e values were obtained as Q₁ = 0.63, e₁ 1.07. It was found that all the polymers and copolymers showed a strongly negative circular dichroism (CD) peak at about 258 nm. From the results of chirality of the copolymer, it was concluded that induction of asymmetric carbon atoms into the MBZCI-ST copolymer main chain took place.