Kooyman, E. C.; Wibaut, J. P. published the artcile< Pyridine and quinoline derivatives. LX. The orientation of the CO2C2H5 group in the condensation product of malonic ester and β-aminocrotonic acid ester>, Product Details of C9H9Cl2NO2, the main research area is .
In the 2-methyl-4,6-dihydroxypyridinecarboxylate described by Knoevenagel and Fries (Ber. 31, 767(1898)), the position of the carboxylate group was unknown. The location of this group at 5 rather than at 3 was established by the following reactions: The original condensation product, heated with POCl3 at 120° in a sealed tube for 4 hrs., yielded a mixture of the acid chloride (I) and the Et ester (II) of 2-methyl-4,6-dichloro-5-pyridinecarboxylic acid, which could be separated by fractional distillation at 1 mm. The first fraction b. 97-104°, and after a 2nd distillation was obtained as a clear, colorless oil which solidified at 14.8°. The analyses agreed fairly well with C7H4ONCl3. On heating with H2O, HCl was split off, and the free acid was obtained. The compound was therefore believed to be I. The 2nd fraction b. 113-16°. It was obtained in 30% yield as white needles, m. 56° (50% EtOH), which were readily soluble in Et2O and EtOH, and sparingly soluble in H2O. It was identified as II. The free acid obtained from the ester by saponification m. 151.5° (dilute HCl) and was slightly soluble in H2O, very slightly soluble in HCl, but readily soluble in Et2O and EtOH. By catalytic reduction of II in absolute EtOH with Pd chloride and KOAc, the Cl was removed, and Et 2-methyl-5-pyridinecarboxylate (III) was obtained in 72% yield as a colorless oil b2 97° (Graf, C.A. 26, 1932). By saponification of III with KOH, preparation of the Cu salt, and decomposition with H2S, the free acid (IV) was obtained. It was purified by sublimation at 180°/35 mm. and m. 209-10°. It was identified by mixed m.p. with a sample prepared from 2-methyl-5-ethylpyridine. The amide (V), m. 196°, was prepared from III by shaking with NH3 according to the method of Graf. The picrate of the ester m. 170-1° (light yellow needles from alc. picric acid). The amide and the picrate showed no m.p. depression when mixed with the corresponding amide and picrate prepared from the ester obtained from 2-methyl-5-ethylpyridine.
Recueil des Travaux Chimiques des Pays-Bas et de la Belgique published new progress about 86129-63-7. 86129-63-7 belongs to class pyridine-derivatives, and the molecular formula is C9H9Cl2NO2, Product Details of C9H9Cl2NO2.