Gas-phase basicity of polyfunctional amidinazines: Experimental evidence of preferred site(s) of protonation

Authors
Raczynska, ED Decouzon, M Gal, JF Maria, PC Taft, RW Anvia, F
Citation
Ed. Raczynska et al., Gas-phase basicity of polyfunctional amidinazines: Experimental evidence of preferred site(s) of protonation, J ORG CHEM, 65(15), 2000, pp. 4635-4640
Citations number
35
Categorie Soggetti
Chemistry & Analysis","Organic Chemistry/Polymer Science
Journal title
JOURNAL OF ORGANIC CHEMISTRY
ISSN journal
00223263 → ACNP
Volume
65
Issue
15
Year of publication
2000
Pages
4635 - 4640
Database
ISI
SICI code
0022-3263(20000728)65:15<4635:GBOPAE>2.0.ZU;2-#
Abstract
Gas-phase basicities of four polyfunctional N-1,N-1-dimethyl-N-2-azinylform amidines (1-4) are obtained from proton-transfer equilibrium constant deter minations, using Fourier transform ioncyclotron resonance mass spectrometry . Comparison with model amidines and azines (GB revised according to the re cent compilation of Hunter and Lias) indicates the aza group as the favored site of protonation. The strong basicity of ortho derivatives is explained in term of intramolecular stabilization (the so-called "internal solvation ").