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The determination of the COOH substiuent effect for branched carboxylic acids from carbon-13 chemical shifts

✍ Scribed by David H. Marr

Publisher: John Wiley and Sons
Year: 1980
Tongue: English
Weight: 330 KB
Volume: 13
Category: Article
ISSN: 0749-1581
DOI: 10.1002/mrc.1270130107

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✦ Synopsis

Abstract

The carboxyl substituent effects for branched carboxylic acids have been determined by carbon‐13 Fourier ransform nuclear magnetic resonance of eighteen measured and reported branched acids. For α‐branched systems the substituent effects are α = 15.3 ppm, β = 2.6 ppm, γ = −1.9 ppm, δ = 0.9 ppm and ϵ = 0.5 ppm. For other branched acids, the determined carboxyl substituent effects are α = 19.2 ppm, β = 2.1 ppm, γ = −1.4 ppm, δ = 0.6 ppm, and ϵ = 0.6 ppm.

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