Boron tribromide → (Rac)-4-bromo-2-[7-oxo-4-(3-trifluoromethyl-phenyl)-[1,4]diazepan-1-yl]-butyric acid methyl ester

HRID 1096215Notes

Reaction equation

HRID 1096215 reaction equation
[CH3:1][O:2][C:3](=[O:33])[CH:4]([N:15]1[C:21](=[O:22])[CH2:20][CH2:19][N:18]([C:23]2[CH:28]=[CH:27][CH:26]=[C:25]([C:29]([F:32])([F:31])[F:30])[CH:24]=2)[CH2:17][CH2:16]1)[CH2:5][CH2:6]O[Si](C(C)(C)C)(C)C.B(Br)(Br)[Br:35]>C(Cl)Cl>[CH3:1][O:2][C:3](=[O:33])[CH:4]([N:15]1[C:21](=[O:22])[CH2:20][CH2:19][N:18]([C:23]2[CH:28]=[CH:27][CH:26]=[C:25]([C:29]([F:32])([F:31])[F:30])[CH:24]=2)[CH2:17][CH2:16]1)[CH2:5][CH2:6][Br:35]

Participants

4

Reactant 2

HCID 25134Boron tribromide2×HCID 66783316(Rac)-4-(tert-butyl-dimethyl-silanyloxy)-2-[7-oxo-4-(3-trifluoromethyl-phenyl)-[1,4]diazepan-1-yl]-butyric acid methyl ester

Product 1

HCID 66783270(Rac)-4-bromo-2-[7-oxo-4-(3-trifluoromethyl-phenyl)-[1,4]diazepan-1-yl]-butyric acid methyl esterYield 11%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

A solution of 1.03 g (2.12 mmol) of (rac)-4-(tert-butyl-dimethyl-silanyloxy)-2-[7-oxo-4-(3-trifluoromethyl-phenyl)-[1,4]diazepan-1-yl]-butyric acid methyl ester in 6 ml of CH2Cl2 was treated at 0° C. with 2.33 ml (2.33 mmol, 1M in CH2Cl2) of boron tribromide and kept 2.5 h at this temperature. The solution was warmed to RT cooled (0° C.) and treated again with 2.33 ml (2.33 mmol, 1M in CH2Cl2) of boron tribromide. After 1 h at this temperature, the reaction was extracted with cold sat. aq. NaHCO3 and EtOAc solution (3×). The organic phases were washed with sat. aq. NaHCO3 solution, dried over Na2SO4 and evaporated to give 1.14 g of the crude compound. Purification by flash silica gel column ((n-heptane:EtOAc 95:5, 1:1 to EtOAc) gave 0.086 g (11%) of the title compound as light yellow oil, MS: 437.1 (MH+, 1Br) and

Workup

  1. temperaturecooled (0° C.)
  2. waitAfter 1 h at this temperature
  3. extractionthe reaction was extracted with cold sat. aq. NaHCO3 and EtOAc solution (3×)
  4. washThe organic phases were washed with sat. aq. NaHCO3 solution
  5. dry with materialdried over Na2SO4
  6. customevaporated
  7. customto give 1.14 g of the crude compound
  8. customPurification by flash silica gel column ((n-heptane:EtOAc 95:5, 1:1 to EtOAc)

Sources & evidence

ORD record
ord-081f4a953c044abca8dd3675eb901d37
Source dataset
uspto-grants-2012_03
Patent number
US08138175B2

Reaction notes

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