Theoretical study on photolysis of half-parent type diazomethane

Abstract

Half-parent type diazomethane (EMind)CHN2 having a bulky steric protecting group (Rind: octa-R-substituteds-hydrindacene; EMind) is expected for the synthesis of silyne having acarbon-silicon triple bond. Since diazomethanes generate highly reactivecarbene by photolysis, controlling the carbene reaction is the key tosynthesize silyne. In this study, we investigated the photoreactions ofhalf-parent type diazomethane using density functional theory (DFT)and time-dependent density functional theory (TD-DFT). First, we used phenyldiazomethane (PhCHN2) as a modelmolecule, and searched for the reaction paths on ground state using theartificial force induced reaction (AFIR)method which is proposed as an automatic reaction path search method. Next, weanalyzed the molecular orbitals involved in the photoexcitation of diazomethaneusing the TD-DFT method. And, it is also introduced a method for searching fora crossing of tow potential energy surfaces, such as conical intersections (CI)and intersystem crossing (ISC).