Imidazoles 4.5- dicyano

Imidazole, 2,4(5)-dibromo-l-methyl-rate constants, 5, 400 (78JCS(P2)865, 74AJC233I) Imidazole, 4,5-dibromo-1-methyl-rate constants, 5, 400 (78JCS(P2)865, 74AJC233I) Imidazole, 4,5-dicyano-pKa, 5, 384 (B-76MI40701, 70AHC(I2)I03, 80AHC(27)24I>... 

Imidazole, 4,5-dibromo-l-methyl-synthesis, S, 399 Imidazole, 4,5-di-t-butyl-synthesis, S, 483 X-ray diffraction, S, 350 Imidazole, 4,5-dichloro-chlorination, S, 398 synthesis, S, 398, 473 Imidazole, 4-(3,4-dichlorophenyl)-nitration, 5, 433 Imidazole, 4,5-dicyano-hydrolysis, S, 435-436 synthesis, S, 461, 472, 487 Imidazole, 4,5-dicyano-1-vinyl-synthesis, S, 387 Imidazole, 4,5-dihydro-mass spectra, 5, 360 Imidazole, 4-(dihydroxybutyl)-synthesis, S, 484 Imidazole, 4,5-diiodo-nitration, S, 396 synthesis, S, 400 Imidazole, 2,4-diiodo-5-methyl-iodination, S, 400 Imidazole, 1,2-dimethyl-anions... 

Imidazole, l,2,5-trimethyl-4-nitro-mass spectra, 5, 359 Imidazole, 1-trimethylsilyl-reactions, 5, 454 with acid chlorides, 5, 391 Imidazole, 1-trimethylstannyl-reactions, 5, 454 Imidazole, 2,4,5-trinitro-reactions, 5, 98 synthesis, 5, 395 Imidazole, 1,2,4-triphenyl-UV spectra, 5, 356 Imidazole, 1,2,5-triphenyl-UV spectra, 5, 356 Imidazole, 2,4,5-triphenyl-chemiluminescence, 5, 381, 406 irradiation, 5, 433 oxidation, 5, 376, 406 photochemical addition reactions, 5, 421 synthesis, 5, 467, 483 UV spectra, 5, 356, 357 Imidazole, 1-trityl-rearrangement, 5, 377 Imidazole, vinyl-Michael addition, 5, 437 polymers, 1, 281 Imidazole, 1-vinyl-reactions, 5, 450 thermal rearrangement, 5, 450 Imidazole, 2-vinyl-oxidation, 5, 437 Imidazole, l-(D-xylofuranosyl)-synthesis, 5, 491 277-Imidazole, 2,2-dialkyl-rearrangement, 5, 422 277-Imidazole, 4,5-dicyano-2,2-dimethyl-synthesis, 5, 472... 

Acetylene derivatives are useful starting materials for the preparation of heterocyclics, e.t. thiazoles and imidazoles . Dicyano-... 

The tetracyano derivative of 2.49, 5-diazo-l,2,3,4-tetracyanocyclopentadiene (2.52), and its heterocyclic analogue, 2-diazo-4,5-dicyano-imidazole (2.53) can be obtained by diazotization of the corresponding amines, namely the (anionic) 1-amino-... 

Khashaba et al. [34] suggested the use of sample spectrophotometric and spectrofluorimetric methods for the determination of miconazole and other antifungal drugs in different pharmaceutical formulations. The spectrophotometric method depend on the interaction between imidazole antifungal drugs as -electron donor with the pi-acceptor 2,3-dichloro-5,6-dicyano-l,4-benzoquinone, in methanol or with p-chloranilic acid in acetonitrile. The produced chromogens obey Beer s law at Amax 460 and 520 nm in the concentration range 22.5-200 and 7.9-280 pg/mL for 2,3-dichloro-5,6-dicyano-l,4-benzoquinone and p-chloranilic acid, respectively. Spectrofluorimetric method is based on the measurement of the native fluorescence of ketoconazole at 375 nm with excitation at 288 nm and/or fluorescence intensity versus concentration is linear for ketoconazole at 49.7-800 ng/mL. The methods... 

With chlorinated quinones. New heterocycles containing 1,2-dihydro-imidazo [l,2- ]imidazol-3-one 405 or 1/7-imi-dazo[l,2- ]pyrazole moieties were obtained via charge-transfer interaction of creatinine or 3-aminopyrazole with some 7i-deficient compounds such as 2,3-dichloro-5,6-dicyano-l,4-benzoquinone, 2,3,5,6-tetrachloro-l,4-benzoquinone, 2,3-dichloro- or 2,3-dicyano-1,4-naphthoquinone, and 3,4,5,6-tetrachloro-l,2-benzoquinone (Equation 183) C1996BSB159, 2001HC0541, 2000PS1>. 

Aldehydes condense with DISN to give 2-alkylimidazoles, but in low yield (73USP37099(X)). A related reaction with ketones produces 2,2-dialkyl-4,5-dicyano-2//-imidazoles. When one alkyl group is methyl and the other is a... 

Careful choice of reaction conditions also allows 2-lithiation of imidazoles even in the presence of groups susceptible to attack by the reagent. At -100°C in THF 4,5-dicyano-l-methylimidazole forms the 2-lithio compound at -80°C butyllithium attacks one of the nitrile functions (92JHC1091). 1-Alkoxyimidazoles are lithiated by n-butyllithium (THF, -78°C) at the 2-position (98JOC12). 

Syntheses of fused mesoionic heterocycles such as [l,2,3]triazolo[l,5-a]-quinoline, -quinazoline, -quinoxaline, and -benzotriazine derivatives have been described <02T3185>. Cyclizations of alkyl 2-benzoylamino-(4,5-dicyano-1 //-1,2,3-triazol-1 -yl)propenoates gave [1,2,3]triazolo[l, 5-a]pyrazines <02H(56)353>. Reaction of triethyl N-( 1 -ethy 1-2-methy 1-4-nitro-l//-imidazol-5-yl)phosphorimidate with aryl isocyanates provided a route to 2-aryI-2//,4//-imidazo[4,5-fif][l,2,3]triazoles <02JCS(P 1)1968>. 2-(A,A-Diphenylamino)-4-hydrazino-6-... 

Ac, acetyl AIBN, azobis(isobutanonitrile) All, allyl AR, aryl Bn, benzyl f-BOC, ferf-butoxycarbonyl Bu, Butyl Bz, benzoyl CAN, ceric ammonium nitrate Cbz, benzyloxycarbonyl m-CPBA, m-chloroperoxybenzoic acid DAST, diethylaminosulfur trifluoride DBU, l,8-diazabicyclo[5.4.0]undec-7-ene DCC, /V. /V - d i eye I oh e x y I c ar bo -diimide DCM, dichloromethyl DCMME, dichloromethyl methyl ether DDQ, 2,3-dichloro-5,6-dicyano-l,4-benzoquinone DEAD, diethyl azodicarboxylate l-(+)-DET, L-(+)-diethyl tartrate l-DIPT, L-diisopropyl tartrate d-DIPT, D-diisopropyl tartrate DMAP, 4-dimethylaminopyridine DME, 1,2-dimethoxyethane DMF, /V./V-dimethylformamide DMP, 2,2-dimethoxypropane Et, ethyl Im, imidazole KHMDS, potassium hexamethyldisilazane Me, methyl Me2SO, dimethyl sulfoxide MOM, methoxymethyl MOMC1, methoxymethyl chloride Ms, methylsulfonyl MS, molecular sieves NBS, N-bromosuccinimide NIS, /V-iodosuccinimide NMO, /V-methylmorpho-line N-oxide PCC, pyridinium chlorochromate Ph, phenyl PMB, / -methoxvbenzyl PPTs, pyridiniump-toluenesulfonate i-Pr, isopropyl Py, pyridine rt, room temperature TBAF, tetrabutylammonium fluoride TBS, ferf-butyl dimethylsilyl TBDMSC1, f-butylchlorodimethylsilane Tf, trifhioromethylsulfonyl Tf20, trifluoromethylsulfonic anhydride TFA, trifluoroacetic acid THF, tetrahydrofuran TMS, trimethylsilyl TPAP, tetra-n-propylammonium perruthenate / -TsOH. / -toluenesulfonic acid... 

Hydrolysis of 4,5-dicyanoimidazole yields 4-amino-5-imidazole-car-boxamide which is converted by hypobromite into 4-amino-5-imidazole carbonitrile.444 Hydrolysis of the dicyano compound with aqueous alkali yields the corresponding 4,5-dicarboxylic acid.156 Reduction of the dicyanide with lithium aluminum hydride occurs with greater ease when the imino nitrogen carries a methyl substituent.156... 

The only experimental AEq measured for either of the two low-spin complexes is for the dicyano complex. Our calculated value of 2.31 mm/sec for the S = 1/2 spin state is in poor agreement with the experimental value (53) of 0.35 mm/sec. However, the reported experimental AEq seems to be anomolously low for what is considered to be a low-spin complex. There is apparently no experimental AEq measured for the [Fe(TPP)(N )(py)] complex. The calculated value of 2.19 mm/sec for the doublet state is, however, in good agreement with the experimental values (53) of 2.45 and 2.25 mm/sec for CCP-N3 and MMB-N3, respectively, which differ only by one axial ligand being an imidazole rather than pyridine. This provides further evidence that [Fe(TPP)(N )(py)] has a doublet ground state. 

The zwitterion, or carbene, derived from 4,5-dicyano-2-diazoimidazole reacts with acetic acid to give 4,5-dicyanoimidazolin-2-one (79JOC1717). Photolysis of 4-amino-5-cyanoimidazole gives l,6-dihydroimidazo[4,5-d]imidazole (207 Scheme 109) (74JA2010). 

If DAMN is mono-N-alkylated before reaction with the carbonyl reagent the method gives 1-alkylimidazoles [15]. For example, 4,5-dicyano-l-(2, 3, 5 -tri-0-benzoyl-)S-D-ribofuranosyl)imidazole (57%) has been made by treatment of the ribosylamino-DAMN with triethyl orthoformate at 90°C in anisole under nitrogen for 5h. The intermediate enamine is not isolated in this case [42]. When DAMN is treated with AyV-dialkylamides in the presence of phosphoryl chloride, the Schiff base (14) (R = NR R ) cyclizes to give 2-dialkylaminoimidazoles (15) (R = NR R ), including 4,5-dicyanoimidazole (15) (R = H) when DMF is used [15], Imidazoles (15) (R = OR, NR R ) can be made in one step when DAMN reacts with orthoesters or iminoether hydrochlorides. Under mild reaction conditions the intermediate alkoxyimines (14) (R = OR" ) or amidines (14) (R = NR R ) can be isolated before oxidation to (15) [46, 47, 49], Table 2.1.4 lists some examples. 

The imidatc (27) reacts at 100°C with excess triethyl orthoformate to give 4,5-dicyano-l-ethylimidazole after vacuum distillation. The reaction becomes economically competitive with other reactions which alkylate 4,5-dicyanoimidazole since the 1-alkyl-4,5-dicyanoimidazoles can be made in one-pot reactions merely by heating DAMN at 100°C with excess ortho ester. No co-solvent is necessary. Presumably, (27) forms first, then 4,5-dicyanoimidazole, then the 1-alkyl derivative, with the anion of 4,5-dicyanoimidazole probably being the reactive species. Imidazole itself is not N-alkylatcd by ortho esters instead it induces alkoxidc displacement to give amide acetals [34]. 

Thermolysis of 2-diazo-4,5-dicyano-2//-imidazole 656 in benzonitrile gives nitrilium ylide 657, which reacts with a second benzonitrile molecule to afford [4+2]-cycloadduct 658 (79JOC1717). Intermediate formation of nitrile ylide 659 was also supported in a reaction of N-fluoropyridinium... 

Ac AIBN 9-BBN Bn Boc Bu Bz CAN Cbz CD CSA DABCO DAST DBN DBU DCC DDQ DEAD DHP DIAD DIBAL-H DMAP DME DMF DMP DMSO DNB EE Ee Eq Et Fmoc GLC HLADH HMDS HMPA HOBt HPLC Im acetyl 2,2/-azobisisobutyronitrile 9-borabicyclo[3.3.1]nonane benzyl f-butoxycarbonyl butyl benzoyl ceric ammonium nitrate benzyloxycarbonyl circular dichroism camphorsulfonic acid 1.4- diazabicyclo[2.2.2]octane A,A-Diethylaminosulfur trifluoride 1.5- diazabicyclo[4.3.0]non-5-ene l,8-diazabicyclo[5.4.0]undec-7-ene A,A -dicyclohexylcarbodiimide 2.3- dichloro-5,6-dicyano-1,4-benzoquinone diethyl azodicarboxylate 3.4- dihydro-2//-pyrane diisopropyl azodicarboxylate diisobutylaluminum hydride 4-A,A -dimethylaminopyridine 1,2-dimethoxyethane A,A -dimethylformamide Dess -Martin periodinane [1,1,1 -tris(acetyloxy)-1,1 -dihydro-1,2-benziodoxol-3-( IH) -one] dimethyl sulfoxide 3.5- dinitrobenzoyl 2-ethoxyethyl enantiomeric excess molar equivalent ethyl 9-fluorenylmethoxycarbonyl gas-liquid chromatography horse liver alcohol dehydrogenase 1,1,1,3,3,3 -hexamethyldisilazane hexamethylphosphoric triamide 1 -hydroxybenzotriazole high-performance liquid chromatography 1-imidazolyl or imidazole... 

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