Gas-Phase Fragmentation of Deprotonated p-Hydroxyphenacyl Derivatives

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• 作者：Marek Remes虒 ; Jana Roithova虂 ; Detlef Schro虉der ; Elizabeth D. Cope ; Chamani Perera ; Sanjeewa N. Senadheera ; Kenneth Stensrud ; Chi-cheng Ma ; Richard S. Givens
• 刊名：Journal of Organic Chemistry
• 出版年：2011
• 出版时间：April 1, 2011
• 年：2011
• 卷：76
• 期：7
• 页码：2180-2186
• 全文大小：917K
• 年卷期：v.76,no.7(April 1, 2011)
• ISSN：1520-6904

文摘

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 ^{鈭?/sup>O-C₆H₄-C(O)-CH₂-X. Upon collisional activation in the gas phase, these anions inter alia undergo loss of a neutral 鈥淐₈H₆O₂鈥?species concomitant with formation of the corresponding anions X鈭?/sup>. 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 鈥淐₈H₆O₂鈥?suggest three different routes of similar energy demands, involving a spirocyclopropanone, epoxide formation, and a diradical, respectively.}