A NEW GENERAL FRAGMENTATION REACTION IN MASS-SPECTROMETRY - THE HYDROGEN-CARBON, CARBON-CARBON DOUBLE REARRANGEMENT OF 2-HETEROALKYL SUBSTITUTED DIPHENYLMETHYL CATIONS

Diphenylmethyl cations formed by benzylic cleavage of the molecular io ns of ortho heteroalkyl substituted 1,1-diphenylalkanes undergo the do uble rearrangement process (H to C followed by C to C) previously repo rted for ortho-methoxy derivatives, Hence the formation of substituted benzyl (or tropylium) ions allowing this double rearrangement process constitutes an interesting type of fragmentation reaction characteris tic for 1,1-diphenylalkanes bearing ortho substituents (OMe, OEt, OiPr , SMe, NHMe, NMe(2)) which are able to transfer a hydride to the charg ed benzyl carbon of diphenylmethyl cations formed by benzylic cleavage of the molecular ion.