title: Benzyl anion transfer in the fragmentation of N-(phenylsulfonyl)-benzeneacetamides: a gas-phase intramolecular S(N)Ar reaction.
abstract: In this study, we report a gas-phase benzyl anion transfer via intramolecular aromatic nucleophilic substitution (SNAr) during the course of tandem mass spectrometry of deprotonated N-(phenylsulfonyl)-benzeneacetamide. Upon collisional activation, the formation of the initial ion/neutral complex ([C6H5CH2(-)/C6H5SO2NCO]), which was generated by heterolytic cleavage of the CH2-CO bond, is proposed as the key step. Subsequently, the anionic counterpart, benzyl anion, is transferred to conduct the intra-complex SNAr reaction. After losing neutral HNCO, the intermediate gives rise to product ion B at m/z 231, whose structure is confirmed by comparing the multistage spectra with those of deprotonated 2-benzylbenzenesulfinic acid and (benzylsulfonyl)benzene. In addition, intra-complex proton transfer is also observed within the complex [C6H5CH2(-)/C6H5SO2NCO] to generate product ion C at m/z 182. The INC-mediated mechanism was corroborated by theoretical calculations, isotope experiments, breakdown curve, substituent experiments, etc. This work may provide further understanding of the physicochemical properties of the gaseous benzyl anion.
authors: Department of Chemistry, Zhejiang University, Hangzhou 310027, China. panyuanjiang@zju.edu.cn.
authors: Shanshan
authors: S
authors: Shen
authors: Yunfeng
authors: Y
authors: Chai
authors: Yaqin
authors: Y
authors: Liu
authors: Chang
authors: C
authors: Li
authors: Yuanjiang
authors: Y
authors: Pan
mesh_terms: D000081:Acetamides / Q000138:chemical synthesis / Q000737:chemistry*; D000838:Anions / Q000737:chemistry; D001593:Benzyl Compounds / Q000737:chemistry*; D015394:Molecular Structure; D011522:Protons; D011789:Quantum Theory; D013438:Sulfhydryl Compounds / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: D000081:Acetamides; D000838:Anions; D001593:Benzyl Compounds; C000606452:N-(phenylsulfonyl)-benzeneacetamide; D011522:Protons; D013438:Sulfhydryl Compounds