dinitroparaffin resonance forms shows an increased electron density on nitrogen. This would tend to counterbalance the electronegative effect of the second nitro group. At any rate the considerable variation in values for nitroparaffins is almost entirely due to differences in the acid strengths of the nitro forms. forms of the mononitroparaflins because one of the Charlottesville, Virginia
under reflux for 30 minutes. During this time the original deep red color had changed to dark brown. Chilling to 0" and filtering gave 0.43 g. ( 5 5 7 0 ) of 5-nitroanthranilonitrile, m.p. 208-210'.Sublimation a t 140" (0.05 mm.) raised the melting point to 210-211'.The reported31 melting point for this compound is 210".Action of Potassium Hydroxide on 4-Methylthio-6-nitroquinazo1ine.-A solution of 0.5 g. of 4-methylthio-6nitroquinazoline, 1.24 g. of potassium hydroxide, 40 ml. of mater and 60 ml. of purified dioxane was stirred a t room temperature for 2 hours and then evaporated under reduced (31) H. M. A. Hartmans, RCC. Iran. chim., 66, 468 (1946).pressure to a small volume. brown solid which was purified by sublimation a t 140 (0.02 mm.) to give 0.032 g. (9%) of 5-nitroanthranilonitrile, m.p. 210'.Action of Chloroacetic Acid and Potassium Carbonate on 4-Mercapto-8-nitroquinazoline.-Treatment of 1 g. of 4-mercapto-5-nitroquinazoline with chloroacetic acid and potassium carbonate as described above for the 6-nitro is+ mer gave 0.085 g. (11~') of 3-nitroanthranilonitrile in the form of yellow needles, m.p. 125-128'.Vacuum sublimation a t 100" (0.01 mm.) raised the melting point to 137-138'.Using infrared absorbance measurements, values of R are determined at three temperatures for complex formation, through
Values of AH' and A S oFor the series of compounds substituted in the aniline ring, log K values are linearly For the compounds with a substituent in the benzaldehyde ring, a straight lineThe correlation with uf-values suggests the stabilization In the case of the disubstituted compounds, the data hydrogen bonding, between p-nitrophenol and three series of p-substituted benzalaniline derivatives. for the reaction are also calculated.proportional to the Hammett u-constants.is obtained when log K values are plotted against a+-constants.of the hydrogen bond by resonance interaction with the $-substituent. are discussed in terms of an extended form of the Hammett equation.
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