2.3- dihydro-1/7-1,5-benzodiazepine

The reaction of l,l,l-trifluoro-3-hydroxyimino-4-phenyl-2,4-butanedione in diethyl ether gives rise to 2-hydroxy-3-hydroximino-4-phenyl-2-trifluoromethyl-2,3-dihydro-1/7-1,5-benzodiazepine 52 (yield 75%) (Scheme 50). In methanol there results a cleavage of the latter and the formation of 3-trifluoromethyl quinoxalin-2-one (98ZOR405). When heated in a vacuum or boiled in toluene, compound 52 is stable against dehydration and does not lose a water molecule. 

H-2,3-Benzodiazepine, 3,4-dihydro-synthesis, 7, 596, 599 5H-2,3-Benzodiazepine, 4-phenyI-acylation, 7, 602 photochemical reactions, 7, 600 5 H-2,3 - Benzodiazepine, 1,2,3,4-tetrahydro-synthesis, 7, 596... 

A well-studied case of tautomerism is that of l,2-diazepin-4-ones tautomers 47a and 47b were characterized by NMR, the former being the most stable (85JOC2141). 3,5-Dihydro-4//-2,3-benzodiazepin-4-ones exist as 48a and not as 4-hydroxy tautomers 48b (74JHC401). 

The reaction of methyl anthranilate and 3-amino-2-chloropyridine in 1,2,4-trichlorobenzene in the presence of KOt-Bu at 50 °C gave 5,1 l-dihydro-6//-pyrido[2,3-Z)]benzodiazepin-6-one and 6-amino-ll//-pyr-ido[2,l-Z)]quinazolin-l 1-one as a by-product (99BMCL3031). 

Chloro-6-phenyl-1 -methyl-3-hydroxy-1,3-dihydro-2H-1,4-benzodiazepine-2-one... 

A suspension of 45 g 3-phenoxycarbonyloxy-1 -methyl-7-chloro-5-pheny -1,3-dihydro-2H-1,4-benzodiazepin-2-one in 450 ml methanol is treated with stirring, with 43 ml of a solution of dimethylamine in methanol (containlng31 gdimethylamine in 100 ml). Stirring ismaintained at 20°C to 25°C during 5 hours. The reaction mixture is filtered, and the filtrate is diluted with 450 ml water. The precipitate thus formed, is 3-(N,N-dimethylcarbamoyloxy)-1-methy -7-chloro-5-phenyl-1,3-dihydro-2H-1,4-benzodiazepin-2-one, which is collected on a filter, dried and recrystallized from ethyl acetate, and has a melting point of 173°C to 174°C. 

Chemical Name 5-(o-chlorophenyl)-1,3-dihydro-7-nitro-2H-1,4-benzodiazepin-2-one Common Name —... 

Chemical Name 7-chloro-2,3-dihydro-2,2-dihydroxy-5-phenyl-1 H-1,4-benzodiazepine-3-carboxylic acid dipotassium salt... 

A solution of 60 g of chromic anhydride in 40 ml of water was added dropwise to a suspension of 60 g of 2-aminomethyl-1 -methyl-5-chloro-3-(o-fluorophenyl)-indole hydrochloride in 600 ml of acetic acid. The mixture was stirred at room temperature overnight. To the reaction mixture was added 1.1 liters of ether and 1 liter of water and then 800 ml of 28% ammonium hydroxide, in small portions. The ethereal layer separated, washed with water, dried, and concentrated under reduced pressure. The residue (51.8 g) was dissolved in 100 ml of ethanol, and 100 ml of 20% ethanollc hydrogen chloride was added to the solution and the mixture was cooled. The precipitate was collected by filtration to yield 46.5 g of 1 -methyl-7-chloro-5-(o-fluorophenyl)-1,3-dihydro-2H-1,4-benzodiazepine-2-one hydrochloride, melt-... 

A solution of 0.7 g of 2-(2-amino-N-methylacetamido)-5-chlorobenzophenone in 10 ml of a 50% solution (by weight) of diketene in acetone is refluxed for 3 hours and then evaporated to give a brown oil. The oil Is chromatographed on 200 g of silica gel using a 1 1 (by volume) mixture of ethyl acetate cyclohexane 25 ml fractions are collected. Fractions 11-14 are combined, mixed with chloroform, evaporated and triturated with ether to give 0.337 g of 11-chloro-8,12b-dihydro-2,8-dimethy 1-12b-phenyl-4H-[ 1,3]oxazino[3,2-dl [1,4] benzodiazepine-4,7 (6H)-dione as a pale yellow solid, MP 174°C to 176°C. 

Chemical Name 8-Nitro-1,2-dihydro-2-(N-methyl-piperazin-1 -yl)methylene-6-(o-chloro-phenyl)-1 H,4H-imidazo-[ 1,2-a] [ 1,4] -benzodiazepin-1 -one methanesulfonate... 

To a slightly warm suspension of 3-acetoxy-7-chloro-5-(o-chlorophenyl)-1 3-dihydro-2H-1,4-benzodiazepin-2-one thus obtained was added 4N sodium hydroxide solution with stirring. All the solid dissolved and soon a thick white solid precipitated out. The solid was filtered, washed well with water and recrystallized from ethanol. The product was isolated as a solvate with 1 mol of ethanol. When heated it loses the ethanol of solvation and melts at 166°C to 168 C. 

To a suspension of 3.4 g of 3-acetoxy-7-chloro-1,3-dihydro-5-(o-chlorophenyl)-2H-1,4-benzodiazepin-2-one in 80 ml of alcohol was added 6 ml of 4 N sodium hydroxide. After complete solution had taken place a solid precipitated that redissolved upon the addition of 80 ml of water. The solution was acidified with acetic acid to give white crystals. After recrystallization from alcohol the compound melted at192°Cto 194°C. 

Chemical Name 7-Chloro-1 -dihydro-5-phenyl-l (2H)-1,4-benzodiazepin-2-one Common Name Nordiazepam desmethyidiazepam Structural Formula ... 

A) Suspend lOg of 7-chloro-l -dihydro-5-phenyl-2H-1,4-benzodiazepin-2-one 4-oxide in 150 ml of acetic anhydride and warm on a steam bath with stirring until all the solid has dissolved. Cool and filter off crystalline, analytically pure 3-acetoxy-7-chloro-1,3-dihydro-5-phenyl-2H-1 /t-benzodiazepin-2-one, melting point 242°C to 243°C. 

Chemical Name 7-chloro-1,3-dihydro-3-hydroxy-1-methyl-5-phenyl-2H-1,4-benzodiazepin-2-one... 

Acetoxy-7-chloro-1 -methyl-5-phenyl-l, 3-dihydro-2H-1,4-benzodiazepin-2-one Sodium hydroxide... 

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