Substituent Effect on Fragmentations and Ion-Molecule Reactions of Ionized Alkyn Alcohols

Bulletin of the Korean chemical society

Sung-Seen Choi¹  Hun-Young So¹  Beom-Tae Kim¹ 

关键词: Dehydration;    Deacetylenylation;    Ion-molecule reaction;    2-Propyn-1-ol;    2-Methyl-3-butyn-2-ol;   

DOI  :  

学科分类：化学（综合）

来源: Korean Chemical Society

【 摘 要 】

The fragmentation patterns and ion-molecule reactions of two alkyn alcohols, 2-propyn-1-ol (HC≌CCH₂OH) and 2-methyl-3-butyn-2-ol (HC≌CC(CH₃)₂OH), were investigated using Fourier transform mass spectrometry (FTMS). The most abundant fragment ions formed from the molecular ions were [M-H]⁺ for 2-propyn-1-ol and [M-CH₃]⁺ for 2-methyl-3-butyn-2-ol. The dehydrated ion, [M-H₂O]⁺ was formed only from 2-propyn-1-ol in which �?-hydrogen atoms were available for �?, �?-elimination reaction. The protonated molecules were dissociated into [M+H-H₂O]⁺ and [M+H-C₂H₂]⁺ through dehydration and deacetylenylation processes. The formations of [M+H-H₂O]⁺ and [M+H-C₂H₂]⁺ from 2-methyl-3-butyn-2-ol were more favorable than those from 2-propyn-1-ol due to stabilization by two methyl groups at �?-carbon. Ion-neutral complexes formed at long ion trapping time gave dehydrated and/or deacetylenylated ion products by further dissociation.

【 授权许可】

Unknown