Abstract:

Mass spectrometry experiment is an important course in instrumental chemistry. Based on our long-term practical exploration, we chose Methyl salicylate (methyl o-hydroxy Methyl benzoate) as the experimental object for mass spectrometry analysis, and compared it with its isomers 3-Hydroxybenzoic acid methyl ester, nipagin methyl ester (methyl 4-Hydroxybenzoic acid), vanillin (3-nenenebe methoxy 4-hydroxy Benzaldehyde), 2, 4-dihydroxy Acetophenone and 3, 4-dihydroxy Acetophenone. Through this experiment, students will master the mass spectrum pyrolysis characteristics of benzene ring, carbonyl group, Methoxy group, aldehyde group, phenols etc., and become familiar with the molecular rearrangement phenomenon of "Alpha effect of aromatic ring". This experiment is practical, interesting with moderate difficulty. It can help students to consolidate theoretical knowledge and exercise thinking, improving practical application ability. It is suitable for students major in pharmacy, chemistry, food or other related ones, and also can be used as experimental training materials for graduate students.

Key words: Mass spectrometry experiment, Methyl salicylate, Molecular rearrangement, Thinking training