Reaction pathways of direct O and S atoms abstraction from oxirane and thiirane by silylidene: A theoretical study

The mechanisms for the abstraction reactions of silylidene with oxirane and thiirane have been characterized in detail using density functional theory as well as the ab initio method, including zero-point corrections. According to the model calculations, whether for oxirane or thiirane the reaction will easily yield syn-/anti-isomer mixture. Furthermore, the syn-H2CSiOC2H4 and syn-H2CPSiSC2H4 can form approximately linear products (P1 and P4); however, anti-H2CSiOC2H4 and anti-H2CSiSC2H4 lead to three-membered ring silylenes (P2 and P5), and then the three-membered ring silylenes (P2 and P5) will further yield the more stable compounds (P3 and P6).