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Gas-phase fragmentation of deprotonated p-hydroxyphenacyl derivatives.

ABSTRACT: Electrospray ionization of methanolic solutions of p-hydroxyphenacyl derivatives HO-C(6)H(4)-C(O)-CH(2)-X (X = leaving group) provides abundant signals for the deprotonated species which are assigned to the corresponding phenolate anions (-)O-C(6)H(4)-C(O)-CH(2)-X. Upon collisional activation in the gas phase, these anions inter alia undergo loss of a neutral "C(8)H(6)O(2)" 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 = CF(3)COO in order to reveal the energetically most favorable pathway for the formation of neutral "C(8)H(6)O(2)" suggest three different routes of similar energy demands, involving a spirocyclopropanone, epoxide formation, and a diradical, respectively.

SUBMITTER: Remes M

PROVIDER: S-EPMC3065380 | biostudies-literature | 2011 Apr

REPOSITORIES: biostudies-literature

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Gas-phase fragmentation of deprotonated p-hydroxyphenacyl derivatives.

Remeš Marek M Roithová Jana J Schröder Detlef D Cope Elizabeth D ED Perera Chamani C Senadheera Sanjeewa N SN Stensrud Kenneth K Ma Chi-cheng CC Givens Richard S RS

The Journal of organic chemistry 20110308 7

Electrospray ionization of methanolic solutions of p-hydroxyphenacyl derivatives HO-C(6)H(4)-C(O)-CH(2)-X (X = leaving group) provides abundant signals for the deprotonated species which are assigned to the corresponding phenolate anions (-)O-C(6)H(4)-C(O)-CH(2)-X. Upon collisional activation in the gas phase, these anions inter alia undergo loss of a neutral "C(8)H(6)O(2)" species concomitant with formation of the corresponding anions X(-). The energies required for the loss of the neutral roug ...[more]

PMID: 21384805

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Dataset Information

Gas-phase fragmentation of deprotonated p-hydroxyphenacyl derivatives.

Publications

Gas-phase fragmentation of deprotonated p-hydroxyphenacyl derivatives.

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