Carboxylic acid derivatives spectroscopic analysis

The bicyclo[5,3,l]undec-7-ene-ll-one-l-carboxylic acid derivative (77) represents a case close to the limit for the possible existence of a bridgehead double bond. Unusual chemical and spectroscopic properties had suggested incomplete conjugation of the a -enone system, and this is confirmed by the analysis of (77) which reveals that the C(8)-C(7)-C(l l)-0 torsion angle is 37.6°. This value is in good agreement with the angle of 40° which had been predicted from an empirical examination of the u.v. spectrum. 

Tetrahedral intermediates, derived from carboxylic acids, spectroscopic detection and the investigation of their properties, 21, 37 Thermodynamic stabilities of carbocations, 37, 57 Topochemical phenomena in solid-state chemistry, 15, 63 Transition state analysis using multiple kinetic isotope effects, 37, 239 Transition state structure, crystallographic approaches to, 29, 87 Transition state structure, in solution, effective charge and, 27, 1 Transition state structure, secondary deuterium isotope effects and, 31, 143 Transition states, structure in solution, cross-interaction constants and, 27, 57 Transition states, the stabilization of by cyclodextrins and other catalysts, 29, 1... 

In addition to functionalization of polyanilines with sulfonic and carboxylic acids, the corresponding phosphonic acid derivatives have been prepared, o-Aminobenzylphosphonic acid was prepared as shown in Figure 20.54 [42,43]. Oxidative coupling of the above monomer in an acidic medium yielded poly(o-aminobenzylphosphonic acid) (Figure 20.55). Spectroscopic analysis was consistent with head-to-tail oxidative coupling through the /Jara-position. The as-prepared polymer was in its emeraldine oxidation state in which 43% of the N-atoms were protonated by the pendent acid. This polymer was insoluble in both non-aqueous solvents and aqueous acidic solutions. 

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