A substitution on vinylic carbon was investigated by using ab initio molecular orbital calculations at the MP2/6-31+G*//RHF/6-31+G* level of theory. The intrinsic reaction coordinate calculations of 2, 2-difluoro-1-mesyloxyvinyl- (trimethyl) borate showed a possibility that the substitution proceeds through SN1-like mechanism with retention of configuration although the activation energy is as large as 56.2 kcal mol-1 in vacuum and 36.3 kcal mol-1 in THF.
In order to develop a chemical hazard prediction system showing a higher performance than those of existing systems using linear multi-regression analysis as quantitative structure-activity relationship, neural network was applied to the prediction of carcinogenicity of 41 kinds of organic chlorine-containing compounds. Seven kinds of structural descriptors easily determined from molecular structures were used. A leave-one-out test showed a performance of 83%, higher than those of existing systems, and a possibility to get a higher performance was discussed.