Methyl 3-chloro-2-quinoxalinecarboxylate

Methyl 3-chloro-2-quinoxalinecarboxylate (113) gave a separable mixture of A,A -bis(3-methoxycarbonylqumoxalin-2-yl)hydrazine (114) and methyl 3-hydrazino-2-quinoxalinecarboxylate (115) [substrate, H2N1SIH2 H20 ( 1 equiv), EtOH, 20°C 70°C, short time 25% of each product after separation] or 3-hydrazino-2-qumoxalinecarbohydrazide (116) [H2N1SIH2 H20 ( 2.5 equiv), EtOH, 70°C, substrate during 30 min 95%]. °... 

Several recent general papers on the properties of quinoxaline N-oxides have reported studies on the crystal structures of quinoxaline 1,4-dioxide,380 its 2,3-dimethyl derivative,380 ethyl 7-chloro-3-methyl-2-quinoxalinecarboxylate 1,4-dioxide,40 and N-(2-hydroxyethyl)-3-methyl-2-quinoxalinecarboxamide 1,4-dioxide 931 the NMR spectral data of quinoxaline 1,4-dioxide for comparison with those of related dioxides 348 the NMR data for biologically active quinoxalinecarboxamide dioxides 381 thermochemical data for several quinoxaline dioxides 183 and polaro-graphic or cyclic voltammetric data for 2,3-disubstituted quinoxaline dioxides.239 894... 

Benzenediamine (199) and C-(2-chloro-2-phenylacetyl)formamide (200) gave 3-phenyl-3,4-dihydro-2-quinoxalinecarboxamide (201), formulated as its 1,4-dihydro tautomer (EtOH, reflux, 6 h 56%) in contrast, the same substrate (199) with methyl C-(2-chloro-2-phenylacetyl)formate cyanohydrin (202) gave methyl 3-phenyl-2-quinoxalinecarboxylate (203), presumably by aerial oxidation of a dihydro precursor (MeCN, reflux, 12 h 7%). ... 

Methyl 3-chloro-5-methoxy-6,7-dimethyl-2-quinoxalinecarboxylate (111) gave 5-methoxy-6,7,A-trimethyl-3-methylamino-7-quinoxalinecarboxamide (112) (excess MeNH2, MeOH, 150°C, sealed, 7h 85%). " ... 

Methyl 6-chloro-2-quinoxalinecarboxylate Methyl 7-chloro-2-quinoxalinecarboxylate Methyl 3-(2-cyanovinyl)-2-quinoxalinecarboxylate... 

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