The Journal of Organic Chemistry

Hammett and Taft substituent constants for the mesylate, tosylate, and triflate groups

PJ Stang, AG Anderson

Index: Stang,P.J.; Anderson,A.G. Journal of Organic Chemistry, 1976 , vol. 41, p. 781 - 785

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Citation Number: 36

Abstract

The Hammett up values for the mesylate (l), tosylate (2), and triflate groups (3) were determined by titration of the appropriate benzoic acids and found to be $0.33,+ 0.29, and+ 0.47, respectively. Taft UI values were determined by 19F NMR of the appropriately substituted 3-fluorophenylsulfonate esters and found to be 1,+ 0.61; 2,+ 0.54, 3,+ 0.84. By interpolation using pK, data for a number of substituted acetic acids, the value of u* for the ...