7-chloro-5,6-dihydro-5-methyl-6-oxo-4H-imidazo[1,5-a][1,4]benzodiazepine-3-carboxaldehyde → HCID 19851521, compound

HRID 1606957Notes

Reaction equation

HRID 1606957 reaction equation
[CH2:1]([Li])[CH2:2]CC.[Cl:6][C:7]1[C:12]2[C:13](=[O:24])[N:14]([CH3:23])[CH2:15][C:16]3[N:17]([CH:18]=[N:19][C:20]=3[CH:21]=O)[C:11]=2[CH:10]=[CH:9][CH:8]=1>[Br-].C([P+](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1)C.O1CCCC1.CCCCCC>[Cl:6][C:7]1[C:12]2[C:13](=[O:24])[N:14]([CH3:23])[CH2:15][C:16]3[N:17]([CH:18]=[N:19][C:20]=3/[CH:21]=[CH:1]\[CH3:2])[C:11]=2[CH:10]=[CH:9][CH:8]=1.[Cl:6][C:7]1[C:12]2[C:13](=[O:24])[N:14]([CH3:23])[CH2:15][C:16]3[N:17]([CH:18]=[N:19][C:20]=3/[CH:21]=[CH:1]/[CH3:2])[C:11]=2[CH:10]=[CH:9][CH:8]=1

Participants

7

Reactant 2

HCID 198515847-chloro-5,6-dihydro-5-methyl-6-oxo-4H-imidazo[1,5-a][1,4]benzodiazepine-3-carboxaldehydeHCID 178418339Butyllithium

Product 2

HCID 19851521HCID 19851521, compoundHCID 67902304HCID 67902304, compound

Reagents, catalysts & solvents 3

HCID 73727Phosphonium, ethyltriphenyl-, bromide (1:1)CatalystHCID 8028TetrahydrofuranSolvent2×HCID 8058HexaneSolvent

Procedure

15 g (40.4 mmol) of ethyltriphenylphosphonium bromide was placed in 60 ml of tetrahydrofuran and treated dropwise at -40° with 28 ml (45 mmol) of 1.6 molar butyllithium solution in n-hexane. The orange suspension obtained was stirred at -40° for a further 20 minutes and subsequently a solution of 10 g (36 mmol) of 7-chloro-5,6-dihydro-5-methyl-6-oxo-4H-imidazo[1,5-a][1,4]benzodiazepine-3-carboxaldehyde in 250 ml of tetrahydrofuran was added dropwise thereto within 50 minutes at -40° to -50°. The mixture was stirred at room temperature for a further 2 hours and subsequently filtered. The filtrate was evaporated and chromatographed on silica gel while eluting with cyclohexane/ether/isopropanol (3:3:1). There was obtained 7-chloro-4,5-dihydro-5-methyl-3-[(Z)-propenyl]-6H-imidazo[1,5-a][1,4]benzodiazepin-6-one of melting point 169.5°-170.5° (from ethyl acetate/hexane) and 7-chloro-4,5-dihydro-5-methyl-3-[(E)-propenyl]-6H-imidazo[1,5-a][1,4] benzodiazepin-6-one of melting point 200°-201° (from acetonitrile).

Workup

  1. customThe orange suspension obtained
  2. waitwithin 50 minutes at -40° to -50°
  3. stirringThe mixture was stirred at room temperature for a further 2 hours
  4. filtrationsubsequently filtered
  5. customThe filtrate was evaporated
  6. customchromatographed on silica gel
  7. washwhile eluting with cyclohexane/ether/isopropanol (3:3:1)

Sources & evidence

ORD record
ord-5a45ed6f3adc4846afbcf2e0f05bc463
Source dataset
uspto-grants-1989_09
Patent number
US04863920

Reaction notes

Loading…