✦ LIBER ✦

Evaluation of steric and substituent effects in phenols by competitive reactions of dimethyl ether ions in a quadrupole ion trap

✍ Scribed by Gerald F. Bauerle; Jennifer S. Brodbelt

Book ID: 103996802
Publisher: Elsevier Science
Year: 1995
Tongue: English
Weight: 1024 KB
Volume: 6
Category: Article
ISSN: 1044-0305
DOI: 10.1016/1044-0305(95)00229-7

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✦ Synopsis

Competitive reactions of dimethyl ether ions are used to probe the steric and substituent effects of substituted phenols and anisoles in a quadrupole ion trap. The relative percentages of protonation and methylene substitution from the reactions of dimethyl ether ions show a correlation with size, location, and number of substituents on the aromatic ring. Although gas-phase basicity measurements of the phenols show no discernible correlation with the percentages of competitive reactions, semiempirical calculations show a good correlation between the trend in heats of formation and the trend in methylene substitution percentage. Reactions with deuterated compounds show that the methylene substitution reaction occurs on the ring.

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