Mass spectrometry of π‐complexes of transition metals. XIII—The dehydration process and genesis of ions [M–O]⁺⋅ in the mass spectra of cymantrenyl‐, ferrocenyl‐and benchrotrenylcarbinols

Abstract

The mass spectra of a number of cymantrenyl-, ferrocenyl-and benchrotrenyIcarbmois have been siudied. The eiimination of water moledes from íhe d e d a r ious pmceeds by the l,2-elimination mechanism involving hydroxyi transfer to the metal. The [M-16]+ ions originate from thermal decomposiíion of the compounds studied m the iniet system.The elimination, after electron impact of water is characteristic for the fragmentation of aliphatic, alicyclic and aromatic alcohols.2 In aliphatic alcohols the dehydration proceeds maidy as 1,4-elimination via a 6-membered transition state.2 With phenylcarbinols, 1,2-(Zphenylethanol), 1,3-(3-phenylpropanol), 13-(5-phenylpentanol) and even 1,6-(6-phenylhexanol) elimination processes occur? Littie work has been done on hydroxy derivatives of transition metal Tcomplexes. [M -H20]' ions were observed in the m a s spectra of ~ymantrenyl-~ and ferrocenyl-' carbinols; a 1 ,Zelimination mechanism was suggested for the latter compounds.In order to elucidate the dehydration mechanisms of alcohols as ligands in complexes we have studied the mass spectra of cymantrenylcarbinols (la-lf), ferrocenylcdrbinols (2a-2g) and benchrotrenylcarbinols (3% 3b; 4a, 4b).