Pivaloyl chloride → 3-(7-chloro-5,6-dihydro-5-methyl-6-oxo-4H-imidazo[1,5-a][1,4]benzodiazepin-3-yl)-1,1-dimethyl-2-propynyl pivalate

HRID 1493123Notes

Reaction equation

HRID 1493123 reaction equation
[Cl:1][C:2]1[C:7]2[C:8](=[O:23])[N:9]([CH3:22])[CH2:10][C:11]3[N:12]([CH:13]=[N:14][C:15]=3[C:16]#[C:17][C:18]([OH:21])([CH3:20])[CH3:19])[C:6]=2[CH:5]=[CH:4][CH:3]=1.[C:24](Cl)(=[O:29])[C:25]([CH3:28])([CH3:27])[CH3:26]>N1C=CC=CC=1>[C:24]([O:21][C:18]([CH3:20])([CH3:19])[C:17]#[C:16][C:15]1[N:14]=[CH:13][N:12]2[C:6]3[CH:5]=[CH:4][CH:3]=[C:2]([Cl:1])[C:7]=3[C:8](=[O:23])[N:9]([CH3:22])[CH2:10][C:11]=12)(=[O:29])[C:25]([CH3:28])([CH3:27])[CH3:26]

Participants

4

Reactant 2

HCID 62493Pivaloyl chlorideHCID 198306547-chloro-4,5-dihydro-3-(3-hydroxy-3-methyl-1-butynyl)-5-methyl-6H-imidazo[1,5-a][1,4]benzodiazepin-6-one

Product 1

HCID 198306513-(7-chloro-5,6-dihydro-5-methyl-6-oxo-4H-imidazo[1,5-a][1,4]benzodiazepin-3-yl)-1,1-dimethyl-2-propynyl pivalateYield 23.2%

Reagents, catalysts & solvents 1

HCID 1049PyridineSolvent

Procedure

3.30 g (10 mmol) of 7-chloro-4,5-dihydro-3-(3-hydroxy -3-methyl-1-butynyl)-5-methyl-6H-imidazo[1,5-a][1,4]benzo diazepin-6-one were dissolved in 20 ml of pyridine and treated at room temperature with 1.57 g (13 mmol) of pivaloyl chloride. The reaction mixture was stirred at 65° for 24 hours and then evaporated. The residue was taken up in methylene chloride, the solution was washed once with lN hydrochloric acid and twice with water, dried over magnesium sulfate and evaporated. By chromatography on silica gel while eluting with ethyl acetate and subsequent crystallization from ethyl acetate and hexane, there was obtained 0.96 g (23%) of 3-(7-chloro-5,6-dihydro-5-methyl -6-oxo-4H-imidazo[1,5-a][1,4]benzodiazepin-3-yl)-1,1-dimethyl-2-propynyl pivalate of melting point 132-133°.

Workup

  1. customevaporated
  2. washthe solution was washed once with lN hydrochloric acid and twice with water
  3. dry with materialdried over magnesium sulfate
  4. customevaporated
  5. washBy chromatography on silica gel while eluting with ethyl acetate and subsequent crystallization from ethyl acetate and hexane

Sources & evidence

ORD record
ord-6aa1866bf7304fd08de8e449f69cab16
Source dataset
uspto-grants-1991_06
Patent number
US05021411

Reaction notes

Loading…