Ethyl 3-cinnolinecarboxylate

Diethyl 1 -phenyl-1 a,7b-dihydro- [ 1 H -cyclopropa [c] cinnoline-1,1 a-dic arboxylate (194) gave a separable mixture of ethyl 4-(a-ethoxycarbonylbenzyl)-l,4-dihydro-3-cinnolinecarboxylate (195) and ethyl 3-cinnolinecarboxylate (196) (AcOH, reflux, 30 min 40% and 5%, respectively, after separation from... [Pg.28]

A-[2-Ethoxycarbonyl-2-(m-methoxyphenylhydrazono)ethylidene]pyrrolidinium tetrafluoroborate (72) gave ethyl 7-methoxy-3-cinnolinecarboxylate (73) (MeCN, reflux, 60 h 63%). ... [Pg.11]

Morpholinocyclohex-l-ene (150) and ethyl (2,2,2-trichloro-l-phenylethylide-ne)hydrazinecarboxylate (151) gave a separable mixture of ethyl 4-chloro-3-phenyl-l,5,6,7-tetrahydro-l-cinnolinecarboxylate (152, R = C02Et) and 4-chloro-3-phenyl-l,5,6,7-tetrahydrocinnoline (152, R = H) (or tautomer) (EtP4N, CH2CI2, N2, reflux, 5 h 44% and 9%, respectively). - - - ... [Pg.22]

Ethyl l,l-dimethyl-7b-phenyl-la,7b-dihydro-[l//]-cyclopropa[c]cinnoline-lc-carboxylate (192) underwent rearrangement into ethyl 4-isopropenyl-4-phenyl-1,4-dihydro-3-cinnolinecarboxylate (193) (AcOH, reflux, 30 min ... [Pg.28]

Ethyl l,4-dihydro-3-cinnolinecarboxylate (2) gave ethyl 4-bromo-3-cinnoline-carboxylate (3) (substrate, AcOH, then Br2i dropwise, 20°C reflux, 30 min 60% note additional dehydrogenation). " ... [Pg.46]

Ethyl 7-methoxy-4-oxo-l,4-dihydro-3-cinnolinecarboxylate (22, R = H) gave ethyl 1-ethyl-7-methoxy-4-oxo-l,4-dihydro-3-cinnolinecarboxylate (22, R = Et) [Etl, K2CO3 (1 equiv), AcMe, reflux, 8 h 78% (as hydriodide salt) then Et3N, CH2CI2, 20°C, 48 h 91% (as base)]. ... [Pg.62]

Ethyl 6,7-difluoro-4-oxo-l,4-dihydro-3-cinnolinecarboxylate (31) gave a separable mixture of ethyl 6,7-difluoro-l-methyl-4-oxo-l,4-dihydro-3-cinnoline-carboxylate (32) and 3-ethoxycarbonyl-6,7-difluoro-2-methylcmnolin-2-ium-4-olate (33) (substrate, K2CO3, Me2NCHO, 80°C, 30 min, then Me2S04] 80°C, 30 min 62% and 9%, respectively) several pairs of isomers were made... [Pg.64]

Bromo-4-oxo-l,4-dihydro-3-cinnolinecarboxylic acid (34) gave a separable mixmre of 6-bromo-l-methyl-4-oxo-l,4-dihydro-3-cinnolinecarboxylic acid (35, R = Me) and 6-bromo-2-methyl-4-oxo-l,4-dihydrocinnolin-2-ium-3-car-boxylate (36, R = Me) (Me2S04, KOH, H2O, 2TC, 30 min 42% and 43%, respectively, prior to final purification of each) the latter product (36, R = Me) underwent decarboxylation easily to afford 6-bromo-2-methylcin-nolin-2-ium-4-olate (37, R = Me) (recrystaUization from Me2NCHO 33% overall).Ethylation of substrate (34) required more vigorous conditions and afforded a separable mixture of 6-bromo-l-ethyl-4-oxo-l,4-dihydro-3-cinnolinecarboxylic acid (35, R = Et) and 6-bromo-2-ethylcinnolin-2-ium-4-olate (37, R = Et) directly (EtI, EtOH, reflux, 6 h 19% and 18%, respectively, after final purification of each). o... [Pg.64]

Ethyl 4-0X0-l,4-dUiydro-3-cinnohnecarboxylate (41, R = C02Et) gave ethyl 4-thioxo-l,4-dihydro-3-cinnolinecarboxylate (42, R = C02Et) (P2S5, trace... [Pg.65]

Ethyl l-methyl-4-thioxo- underwent virtual hydrolysis to give ethyl l-methyl-4-oxo-l,4-dihydro-3-cinnolinecarboxylate (MeONa, MeOH, Mel, reflux, 5h > 95% mechanism unknown). " ... [Pg.73]

Ethyl 4-thioxo-l,4-dihydro-3-cinnolinecarboxylate (2, R = H) underwent desulfurization to give ethyl l,4-dihydro-3-cinnolinecarboxylate (1, R = H) (Raney Ni, EtOH, reflux, 2 h 25%) ethyl l-methyl-4-thioxo-l,4-dihydro-3-cinnolinecarboxylate (2, R = Me) likewise gave ethyl 1-methyl-1,4-dihy-dro-3-cinnolinecarboxylate (1, R = Me) (40%). ... [Pg.79]

Ethyl (5, R = Et) or methyl 7-chloro-6-fluoro-l-p-fluorophenyl-4-oxo-l,4-di-hydro-3-cinnolinecarboxylate (5, R = Me) gave 7-chloro-6-fluoro-l-p-fluoro-phenyl-4-oxo-l,4-dihydro-3-cinnolinecarboxylic acid (KOH, MeOH, H2O, 50°C 20°C, 2h 96% or 82%, respectively). ... [Pg.96]

Oxo-l,4-dihydro-3-cinnolinecarboxylic acid (21) gave 4-oxo-l,4-dihydro-3-cinnolinecarbonyl chloride (22) (neat SOCI2, reflux, 4 h crude uncharacterized) and thence ethyl 4-oxo-l,4-dihydro-3-cinnolinecarboxylate (23) (EtOH,... [Pg.99]

Ethyl 4-thioxo-l,4-dihydro-3-cinnolinecarboxylate (32) gave 4-amino-3-cinno-linecarboxamide (33) [NH3 gas, EtOH, sealed, 100°C ( ), 18 h 80% note additional aminolysis]. ... [Pg.101]

Ethyl 4-cinnolinecarboxylate (34) gave 4-cinnolinecarbohydrazide (35) (neat HzNNHa-HaO, 20°C 115°C, 90mm >95%) ... [Pg.102]

Ethyl 7-chloro-6-fluoro- l-methyl-4-oxo-1, 4-dihydro-3-cinnolinecarboxylate 178-179, IR, NMR, UV 414... [Pg.363]

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