HYDROBORATION POLYMERIZATION OF DICYANO COMPOUNDS .1. SYNTHESIS OF BORON-CONTAINING POLYMERS BY THE REACTION BETWEEN T-BUBH2.NME3 AND DICYANO COMPOUNDS

A new methodology for the preparation of air-stable boron-containing polymers by the poly-addition between dicyano compounds and t-BuBH2.NMe3 (1) is described. The polyaddition between 1 and isophthalonitrile (2a) was carried out in diglyme under some varied conditions. The molecular weight of the resulting polymer (3a), estimated by GPC, increased when a small excess amount of 1 was used for this polymerization. The structure of 3a was confirmed by H-1, C-13, and B-11 NMR, UV, and IR analyses. The stability of 3a against air and moisture as well as its thermal stability was examined. The boron-containing polymer 3a was found to be stable under air and moisture. As dicyano compounds, telephthalonitrile (2b), 1,5-bis(4,4'-cyanophenoxy)pentane (2c), and alpha,omega-dicyanoalkanes (2d-f) were also used in the present hydroboration polymerization. Among these compounds, the monomers having aromatic cyano groups gave polymers with higher molecular weights.