Ohccho
Formation of Pyrazino 1,2,3-de quinoxalines 194 gave 5-phenyl-2,3-dihydro-1H, 195 COCl 2, Et3N 30 880 also analogs.880,1080 Formation of Pyrazino 2,3-g quinazolines Ethyl 196 and urea gave 3H -dione 197 neat reactants, 198 C, 20 min 92 analogs likewise.
References 1
Information was gleaned from each original publication except where an additional reference to Chemical Abstracts is included. Each citation of a Russian journal or Angewandte Chemie refers to the original Russian or German version, not to any subsequent English translation. Abbreviations for journal titles are those recommended in the Chemical Abstracts Service Source Index 1994 and quarterly supplements. 1. M. J. Grabowski, A. Stepien, M. Cygler, and E. Wajsman, Acta Crystallogr., Sect. B,...
H Mrr
118 underwent deacylation to give 1,3-dimethyl-2 1H -quinoxalinone 119 80 H2NNH2H2O, reflux, 1 h 86 .51 dibromide 120 gave 2,3-dimethyl dibromide 120 gave 2,3-dimethyl
H Vdu
2-Hydroxyaminoquinoxaline self-condensed with loss of 2 x H2O to afford a product, initially formulated as the pentacyclic near-dimer, 170 ,982,992 but subsequently after X-ray analysis as the isomeric 2,2'-azoquinoxaline 170a 62,838 CoCl2 6H2O as template, EtOH, 20 C 90 C, 1 h 74 850,992 or KOH, EtOH, H2O, 20 C, 10 min 56 .838,850 easily prepared in ethanol by catalytic hydrogenation of the corresponding nitro compound afforded the near-dimer, 171 in three steps involving two unisolated...
Info Vqu
D. E. Chasan, L. L. Pytlewski, C. Owens, and N. M. Karayannis, J. Inorg. Nucl. Chem., 1978, 40, 1019. H. Lumbroso, J. Cure, F. Konakahara, and Y. Takagi, J. Mol. Struct., 1980, 68, 293. Z. A. Fataftah, M. R. Ibrahim, and N. H. Al-Said, J. Mol. Struct., 1985, 127, 305. S.-K. Lin and Q.-Z. Cong, J. Mol. Struct., 1987, 159, 279. A. Keyhani and V. A. Veylayan, J. Agric. Food Chem., 1997, 45, 697. G. Jenner and G. Bitsi, J. Mol. Catal., 1988, 45, 165. W. O. Foye, N. Abood, J. M. Kauffman, Y.-H. Kim,...
Info Jtl
extraordinary one-pot reaction between a benzene substrate and no less than three synthons o- tert-butoxycarbonylamino aniline, 3-oxaloindole, 3-phenylpropional-dehye, cyclohexane isocyanide MeOH, 20 C, 24 h evaporation F3CCO2H, CH2Q2, 20 C, 18 h afforded 333 in almost quantitative yield several analogs were made similarly.1088
I Ooq
3-Cyanomethyl-2 1H -quinoxalinone gave 2-chloro-3-cyanomethylquinoxaline 16 POCl3, pyridine, reflux, 15 min 58 .79 2,3 1H,4H -Quinoxalinedione 17 gave 2,3-dichloroquinoxaline 18 neat PCl5, 160 C partial conversion requiring a second such treatment 889 PCl5, POCl3, PhNEt2, reflux, 2.5 h 96 243,263 PCl5, POCl3, reflux, 8h 66 .121
N Gdz
Quinoxaline with dimethyl sulfone or sulfoxide gave 2.2-dioxide 8, n 2 Me2SO2, BuLi, THF, 20 C, 30 min then quinoxaline , 20 C, 4h 82 or the corresponding 2-oxide 8, n 1 Me2SO, likewise 51 , respectively.607 In a somewhat similar way, quinoxaline with N-benzylmethanesulfonamide gave a separable mixture of 2.2-dioxide 9 and 10 MeSO2NHPh, BuLi, THF, 20 C, 1 h then quinoxaline , 20 C, 2h 66 and 15 , respectively the latter product was oxidized to 2- N-benzylsulfamoylmethyl quinoxaline 11 by...
CHO Qml
6.1.1.2. From Dimethylsulfimidoquinoxalines This minor but important route enables a quinoxalinamine to be converted into the corresponding nitroquinoxaline by oxidation of a derived dimethylsulfimido-quinoxaline. Thus 3-chloro-2-quinoxalinamine 24 was converted into 2-chloro-3-dimethylsulfimidoquinoxaline 25 68-88 see Section 6.3.2.4 , which underwent initial oxidation to a green solution of 2-chloro-3-nitrosoquinoxaline 26 m-ClC6H4CO3H, CH2Cl2, -5 C, 40 min then Me2S , 0 C, 10 min and thence...
UV Hvt
Quinoxaline Melting Point C etc. Reference s 6-Styrylquinoxaline trans 100, NMR cis 970 IR E 70 628 or 252-254, E 103 84, 103, 996 223 238 226 2 1H -quinoxalinone 202 202 NMR 1039 221 98 NMR 1039 237 222 NMR 1039 174 174 174 716 22 104 MS 849 97 IR E 203 902 IR, NMR 559 IR 902 105 quinoxalinone IR, MS, NMR E 22 559 NMR E 104 1045 NMR 553 MS, NMR 849 MS, NMR 37 nitroquinoxaline or 192, NMR, E 226, 256 205, 318, 67 1,4-dioxide NMR E 105 718 quinoxalinedione 2,3,5,7-Tetramethylquinoxaline...
R Tml
In a similar way, 4-oxide gave dimethyl 7-chloro- 279, Q Cl, R H 61 460,463 and the isomeric substrate, 1-oxide, gave dimethyl 8-chloro-1 279, Q H, R Cl 50 after separation from a byproduct .489 4-oxide with diethyl 1,3-acetonedi-carboxylate EtO2CCH2COCH2CO2Et gave only one product, formulated on spectral evidence as ethyl 280 or tautomer AcOH, trace H2SO4, reflux, 5 h 80 .513 Formation of Pyridazino 4,5-b quinoxalines Ethyl 1,4-dioxide 281 with hydrazine gave pyridazino 4,5-b quinoxalin-1 2H...
O Jjm
6-Nitroquinoxaline gave a separable mixture of 6-nitroquinoxaline 1-oxide 242 and 6-nitroquinoxaline 4-oxide 243 m-ClC6H4CO3H, CHCl3, 50 C, 18 h 63 and 5 , respectively .161 2-Acetoxymethyl-3-methylquinoxaline gave 2-acetoxymethyl-3-methylquinoxa-line 1,4-dioxide 244 excess m-ClC6H4CO3H, CHCl3, 20 C reflux, 16 h gt 90 .70
H Kjp
198 gave 7,8-dimethylbenzo g pteridine-2,4 1H, 3H -dione 200, R H KOH, MeOH, 20 C, a few hours 83 .66 Methyl 199 gave 3H -dione 200, R Me KOH,