Gas-Phase Fragmentation of Deprotonated p-Hydroxyphenacyl Derivatives

作者：Remes Marek; Roithova Jana^*; Schroeder Detlef; Cope Elizabeth D; Perera Chamani; Senadheera Sanjeewa N; Stensrud Kenneth; Ma Chi cheng; Givens Richard S

来源：Journal of Organic Chemistry, 2011, 76(7): 2180-2186.

DOI：10.1021/jo1025223

Electrospray ionization of methanolic solutions of p-hydroxyphenacyl derivatives HO-C6H4-C(O)-CH2-X (X = leaving, group) provides abundant signals for the deprotonated species which are assigned,to the corresponding phenolate anions O--C6H4-C(O)-CH2-X. Upon collisional activation in the gas phase, these anions inter alia undergo loss of a neutral "C8H6O2" species concomitant with formation of the corresponding anions X-. The energies required for the loss of the neutral roughly correlate with the gas phase acidities of the conjugate acids (HX). Extensive theoretical studies performed for X = CF3COO in order to reveal the energetically most favorable pathway for the formation of neutral "C8H6O2" suggest three different routes of similar energy demands, involving a spirocyclopropanone, epoxide formation, and a diradical, respectively.

• 出版日期2011-4-1