Alford, E. J.; Schofield, K. published the artcile< Cinnolines. XXXI. The nature of the 3-position. Some experiments with 3-substituted cinnolines>, COA of Formula: C19H34O2, the main research area is .
3-Hydroxycinnoline (I) (0.5 g.) and 10 cc. POCl3, refluxed 8 h., decomposed with ice and NaOH, and extracted with Et2O gave 0.05 g. 3-chlorocinnoline (II), m. 90-1°. I (5 g.), 25cc. H2O, and 0.75 g. NaOH in 20 cc. H2O treated at 95° during 10 min. with 4.5 cc. Me2SO4, then with 0.75 g. NaOH in 20 cc. H2O, stirred 20 min., extracted with CHCl3, the extract evaporated, and the residue crystallized from Me2CO gave 3.0 g. 2,3-dihydro-3-oxo-2-methylcinnoline (III), m. 135.5-6.5°, which had a green fluorescence in aqueous solution and decomposed to a tar in hot alkali. A similar experiment with 40 cc. 2N NaOH and 6 cc. Me2SO4 gave a tar which on extraction with hot Me2CO left 0.17 g. insoluble material, crystallizing from alc. or CHCl3-ligroine as the anhydro salt of 3-hydroxy-1-methylcinnolinium hydroxide (IIIa), C9H8ON2, m. 280-3°. I (0.5 g.) dissolved during 0.5 h. in CH2N2-Et2O [from 1 cc. MeN(NO)CO2Et] produced 0.27 g. III; in a similar reaction 0.5 g. 3-hydroxyquinoline (IV) formed 0.57 g. 3-methoxyquinoline [picrate, m. 220-2° (from dioxane)]. Addition of 15 cc. concentrated NH4OH during 0.75 h. to 1 g. III, 20 cc. alc., and 5 g. Zn dust at reflux, refluxing an addnl. 5.25 h., evaporation in vacuo, and crystallization from C6H6-ligroine produced 0.44 g. 1,2,3,4-tetrahydro-3-oxo-2-methylcinnoline, m. 91-2.5°. Refluxing 1 g. III, 1 g. red P, and 10 cc. HI (d. 1.65-1.70) 8 h., cooling, filtering, neutralizing with NaOH, and extracting with Et2O gave 0.45 g. material from which oxindole, m. 125-6.5°, was isolated on recrystallization from H2O, C6H6-ligroine, and finally ligroine; the neutral aqueous solution from the Et2O extraction was made alk. with 20 cc. 4N NaOH and 20 cc. H2O, distilled into 80 cc. 4N HCl, and the distillate evaporated to 0.37 g. MeNH2.HCl, converted with HOAc, ο-C6H4(CO)2O, and anhydrous NaOAc to N-methylphthalimide, m. 133-5° (from HOAc or vacuum sublimation), and to the picrate, m. 208-12° (decomposition) (from EtOAc). pKa values for I (8.64) and IV (8.07) were determined in 0.002M aqueous solution by titration with 0.11N NaOH. IV (0.5 g.), 7 cc. saturated aqueous (NH4)2SO3, and 7 cc. concentrated NH4OH heated 8 h. at 130-40° gave 0.05 g. 3-aminoquinoline (V), m. 80-3° (from PhMe). I was unchanged in the Bucherer reaction. 4-Methylcinnoline, 5 cc. pyridine, and 2.2 g. Cl3CCHO, heated 2 h. at 95° and poured into H2O precipitated 3.85 g. 4-(3,3,3-trichloro-2-hydroxypropyl)cinnoline, m. 165-6° (decomposition) (from EtOH); 3-methylcinnoline (VI) did not give a similar reaction. VI.MeI (VII), m. 204-6.5° (decomposition) (from MeOH), was prepared by refluxing 1.25 g. VI, 1.25 cc. MeI, and 8 cc. EtOH 2.5 h. VII (0.36 g.), 0.25 g. p-Me2NC6H4CHO, and 25 cc. Ac2O, refluxed 2 h. at 160°, produced a small yield of a deeply colored styryl compound, C19H20N3I, m. 353-5° (decomposition) (from alc.), the color of which was destroyed by acid or alkali. 3-Bromocinnoline (VIII) (0.2 g.), refluxed 2 h. with 2 cc. POCl3, was slowly and partially converted to II; the reaction in 3 cc. POCl3 at 95° was slightly more rapid. VIII (0.25 g.) in 3 cc. 5% MeOH-KOH was reduced by refluxing 2 h. with 0.15 g. 5% Pd-C and 0.1 g. 90% N2H4.H2O, diluted with 3 cc. H2O, extracted with Et2O, and converted to 0.15 g. cinnoline picrate, m. 191-4° (from dioxane). VIII (0.5 g.), 0.06 g. CuSO4, and 8 cc. concentrated NH4OH heated 20 h. at 130-40° formed 0.37 g. 3-aminocinnoline (IX), m. 165-6.5° (from EtOAc-ligroine), obtained in the same yield from II at 160-70°. IX, refluxed 5 min. with Ac2O, gave 3-acetamidocinnoline, m. 225-6° (from H2O), but did not seem to form a diazonium salt readily. Heating 0.25 g. VIII and 0.13 g. Na in 4 cc. MeOH 17 h. at 110-20° in a sealed tube gave 0.24 g. crude 3-methoxycinnoline, m. 40-2°, isolated as the picrate, m. 155-7.5° (from alc.); in an experiment on twice the above scale with undried MeOH, the Na salt of I, m. above 270°, was obtained and converted with acid in aqueous solution to 0.25 g. I, m. 200-2°. pKa values for IX (3.63) and V (4.96) were determined in M/90 aqueous solution by titration with 0.91N HCl. UV absorption spectra (λmaximum and λmin., and log ε values given) of I, II, III, IV, and IX in 95% MeOH, 0.01N NaOH, and 0.01N HCl and of I in H2O and IV in 95% EtOH are reported. The evidence for lactam-lactim tautomerism in I and other interaction between the N-2 and the C-3 substituents is discussed.
Journal of the Chemical Society published new progress about Ionization. 112-63-0 belongs to class esters-buliding-blocks, and the molecular formula is C19H34O2, COA of Formula: C19H34O2.
Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics