5- Methyl-2,3-dihydro-l,4-diazepine

Diaminoethane reaets with diaeetylene (0-25°C, 4 h) to form a mixture of tautomers of 5-methyl-2,3-dihydro-l,4-diazepine (4) isolated by sublimation (yield not reported) (69JOC999 77ZC216). 

The reaction of l-dialkylaminobut-l-en-3-ynes 100 with 1,2-diaminoethane (80°C, H" ", 2 h) leads to a mixture of 5-methyl-2,3-dihydro-l,4-diazepine tautomers (4) (the most stable tautomers are shown) (83ZOR1541). 

Dihydro-l,4-diazepines will perform 1,3-dipolar cycloaddition reactions with nitrile oxides and nitrile imines but it is only the imine bonds in the diazepine that react. Thus, 2,3-dihydro-5,7-diphenyl-1-methyl-17/-1,4-diazepine (64 R = Me) only gave mono adducts (65) with arylnitrile... 

CN 5-(2-chlorophenyl)-7-ethyl-1.3-dihydro-l-methyl-2//-thieno[2,3-e]-l,4-diazepin-2-one... 

Chemical Name 5H-Dipyrido(3,2-b 2, 3 -e)(l,4)diazepin-6-one, 5,11-dihydro-ll-cyclopropyl-4-methyl-... 

Reaction of 2,3-dihydro-l,2-diazepin-4-ol 28 with acetic anhydride forms 2-acctyl-5-ructhyM-phcnyl-l, 2-diazabi-cyclo[3.2.0]heptane6-ol 29 in the presence of base and forms 2-acetyl-6-methyl-7-phenyl-2,3-diaza-8-oxabicy-clo[3.2.1]-6-octene 30 in the absence of base. In addition, bicyclic 29 can be transformed into oxadicyclic 30 by treatment with acid. A study using AMI semi-emperical calculations offers several different routes for these... 

The reaction of succinic acid anhydride 111 with 2-methyl-2,4-diphenyl-2,3-dihydroli/-benzo[Z ][l,4]diazepine 112 in toluene in the presence of potassium carbonate leads to 4-(2-methyl-2,4-diphenyl-2,5-dihydro-l/f-l,5-benzodiazepin-5-yl)-4-oxobutanoic acid 113 in 70% yield [110], while its treatment with 2,4-diphenyl-2,3-dihydro-l//-l,5-benzodiazepine 104 follows with chalcone elimination and yields 3-(benzimidazol-2-yl)propionic acid 114 [115] (Scheme 4.36). 

Clotiazepam. 5 (2 Chlorophenyl)-7-ethyl l,3-dihydro-l-methyl-2H-thieno[2,3-e]-I,4-diazepin-2-one Y 6047 Clo/an Rise Rize Rizen Tienor Trecalmo Vera-... 

New amine functionalization reactions have been applied to the functionalization of benzodiazepines, for example, twofold methylation of 2,3,4,5-tetrahydro-lff-benzo[e][l,4]diazepine was achieved using carbon dioxide and phenylsilane with ruthenium catalysis (13AGE9568). A range of readily available 3,4-dihydro-lH-benzo[e][l,4]diazepine-2,5-diones underwent iV-acylation followed by a dehydrative ring-contraction rearrangement process to afford the corresponding oxazoloquinolinones (13OL1052). 

Heating ethylenediamine with methyl 2-chloro-3-nitrobenzoate and Na2C03 in butanol at 80 °C effected a dual S Ar/acylation reaction to afford 9-nitro-3,4-dihydro-177-benzo[f][l,4]diazepin-5(277)-one, an intermediate in the synthesis of inhibitors of poly(ADP-ribose) polymerase-1, in 84% yield (Scheme 55) <2003BMC3695>. 

B) Preparation of 7-Chloro-3-Methoxycarbonyl-5-Phenyl-2-Oxo-2,3-Dihydro-lH-Benzo[f]-l,4-Diazepine (4347 CB) A solution of 9.2 g (0.04 mol) of compound 4356 CB in 20 ml of methanol is added dropwise, in the course of one hour and 30 minutes, to a boiling solution of 9.2 g (0.05 mol) of the hydrochloride of methyl aminomalonate in 30 ml of methanol. When this is completed, heating under reflux is continued for 30 minutes and the product then concentrated to dryness under reduced pressure. The residue is taken up in water and ether, the ethereal layer separated, the product washed with water and dried over sodium sulfate. The solvent is evaporated under reduced pressure. The residue, which consists of the methyl ester, could not be obtained in the crystalline state. It is dissolved in 25 ml of acetic acid, heated under reflux for 15 minutes, the product evaporated to dryness and the residual oil taken up in ether. A colorless solid separates which is filtered by suction and recrystallized from methanol. Colorless crystals are obtained (4.7 9) MPk (Kofler block) 226°C. A second crop (1.5 g) is obtained on concentration of the mother liquor MPk (Kofler block) 222°C total quantity 6.2 g, corresponding to a yield of 47%. 

Chloro-5-(l -Cyclohexenyl)-l-Methyl-2-Oxo-2,3-Dihydro-lH-Benzo[f]Diazepine-l,4 9.7 grams of sodium methylate are added to a solution of 16.5 grams of 7-chloro-5-(l -cyclohexenyl)-2-oxo-2,3-dihydro-lH-benzo[f]diazepine-l,4 dissolved in 120 ml of dry dimethylformamide and the mixture stirred for one-half hour. The reaction mixture is cooled in a water bath and a solution of 33.8 grams of methyl iodide dissolved in 35 ml of anhydrous dimethylformamide is then slowly added with stirring. The solution becomes dark brown in color and a precipitate forms. It is stirred for 2 hours, then diluted with a large volume of water and extracted with ethyl acetate. 

Flash pyrolysis of 5,7-diphenyl-2,3-dihydro-1/7-1,4-diazepine (34, R = H) at 700°C in a vacuum afforded 2-phenylpyrazine (35) in 21% yield, after separation from a pyrimidine the methyl substrate (34, R = Me) also gave a small yield of the same product (35) and 6-phenyl-2,3-dihydro-17/-l,4-diazcpine gave some unsubstituted pyrazine.176,1698... 

Dihydro-5-methyl-6-phenyl-4//-l,2-diazepin-4-one (10) has been prepared1617 by mild acid treatment of 11, 12, or the intermediate bicyclic ketone (13) with very dilute acid or alkali.17 In a... 

Diazepam. 7-Chloro-l,3 dihydro-l methyN5 phenyl-2H-l,4-benzodiazepin-2-one 7-chloro -1 -methy l-S-phenyl-S/f-IA-benzodiazepin-lOJIfJ-one methyl diazepin-one diacepin La 111 Ro 5-2807 Wy 3467 NSC-77518 Alupram Ansiolin Apauiin Apozcpam Atcnsioc Atilen ... 

A) Diazepam (7-Chloro-l,3-dihydro-l-methyl-5-phenyl-2H-l,4-benzo-diazepin-2-one). 

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