Nitrogen-14 nuclear quadrupole resonance of substituted anilines

Abstract

¹⁴ N N.q.r. frequencies for twenty-one substituted anilines are found to be poorly interpreted by the Townes and Dailey theory. Consequently BEEM-π is used to analyse the effect of substituents on the effective field gradient (efg) of the nitrogen atom. The efg is shown to lie at an angle θ to the nitrogen orbital perpendicular to the plane of the aniline ring. CNDO/BW calculations on aniline are reported, and the results used to define the direction of θ. ³⁵Cl N.q.r. frequencies are reported for 4-chloro-3-(trifluoromethyl)- and 2,3-dichloro-aniline.