The Reactivity of Methylene from Photolysis of Diazomethane¹

Insertion of methylene into alkanes

“…However, if CH2 singlet is transformed by collision to the ground-state triplet, discriminate abstraction may be expected.2 As a consequence association of methyl and alkyl radicals may produce the illusion of a more discriminate insertion by CH2 as pointed out by Richardson and coworkers. 20 The elimination of this factor, of course, constitutes the basic reason for scavenging free radicals by addition of NO in the present work as well as in the recent work of Whitten and Rabinovitch9 and by the addition of 02 in the work of Carr.21…”

Photochemical Reactivity of 1,6-Methano[10]annulene

“…We have taken into account the possibility that a solvent molecule might take part in the reaction as a reactant. In fact, it is well-known , that singlet methylene generated from diazomethane by photolysis reacts with a large number of saturated hydrocarbons to produce their methyl derivatives by insertion into the CH bonds. It is reported, for instance, that diazomethane reacts with solvent cyclopentane upon irradiation, giving methylcyclopentane .…”

Recoil chemistry of carbon-11 in C5 hydrocarbons, fragmentation and stabilization

“…which was proposed by Richardson et al (66) to explain carbonhydrogen bond insertion by triplet methylene. The triplet methylene first abstracts a hydrogen atom from the parent gen erating two radicals, one of which is a methyl radical.…”