Boron tribromide → HCID 178435264, compound

HRID 2260385Notes

Reaction equation

HRID 2260385 reaction equation
[Cl:1][CH:2]1[CH:16]([CH2:17][CH3:18])[C:6]2[C:7](=[O:15])[CH:8]=[C:9]([O:13]C)[C:10](=[O:12])[NH:11][C:5]=2[CH2:4][CH:3]1[Cl:19].B(Br)(Br)Br.C([O-])(O)=O.[Na+].[K+].[Br-]>C(Cl)Cl>[Cl:1][CH:2]1[CH:16]([CH2:17][CH3:18])[C:6]2[C:7](=[O:15])[CH:8]=[C:9]([OH:13])[C:10](=[O:12])[NH:11][C:5]=2[CH2:4][CH:3]1[Cl:19]

Participants

6

Reactant 4

HCID 25134Boron tribromideHCID 253877Potassium BromideHCID 516892Sodium BicarbonateHCID 19710531HCID 19710531, compound

Product 1

HCID 178435264HCID 178435264, compound

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent2×

Procedure

To a stirred suspension of 6,7,8,9-tetrahydro-7,8-dichloro-6-ethyl-3-methoxy-1H-1-benzazepine-2,5-dione (525 mg, 1.73 mmol) in dry CH2Cl2 (60 mL, from CaH2) under N2, a solution of BBr3 in CH2Cl2 (10 mL, 1M, Aldrich) was added over 10 s. The suspension turned orange, then a yellow solution was observed which transformed to a yellow suspension. The suspension was allowed to stir under N2 for 1 h. The reaction was added to saturated NaHCO3 (200 mL) and was allowed to stir for 10 min. A pink emulsion was obtained. The emulsion was vacuum filtered (changed filter papers frequently, saved) to give a pink solution. The solution was washed with CH2Cl2 (2×50 mL). The pH of the aqueous portion was adjusted to 2 with concd HCl. The resulting precipitate was collected and washed with water (6×2 mL). The damp filter cake was crystallized from 95% EtOH (dissolved in boiling solvent (100 mL), hot filtered, coned to 40 mL, allowed to cool to rt) to give a pale beige solid (62 mg, 12%, a mixture of diastereomers by NMR (8:2)); mp 197° C. (dec, preheat to 195° C.); tH NMR (DMSO-d6 and D2O) δ0.75 (overlapping t, 3H), 1.22-1.77 (overlapping m, 2H), 2.94 (m, 1H), 3.11 (dd, J1 =4.8 Hz, J2 =17.1 Hz, 1H), 3.37 (overlapping m, 1H), 4.20 (dd, J1 =5.7 Hz, J2 =9.3 Hz, 1H), 4.34-4.61 (overlapping m, 1H), 6.32 and 6.33 (overlapping s, 1H), the spectrum without D2O displayed additional resonances at 10.45 (bs, 1H), 10.99 and 11.05 (overlapping s, 1H); IR (KBr) 3305, 3207, 3097, 2990, 1679, 1647, 1612, 1553, 1399, 1284, 1229, 912 cm-1.

Workup

  1. stirringto stir for 10 min
  2. customA pink emulsion was obtained
  3. filtrationfiltered (
  4. filtrationchanged filter papers frequently
  5. customto give a pink solution
  6. washThe solution was washed with CH2Cl2 (2×50 mL)
  7. customThe resulting precipitate was collected
  8. washwashed with water (6×2 mL)
  9. customThe damp filter cake was crystallized from 95% EtOH (dissolved in boiling solvent (100 mL), hot filtered, coned to 40 mL, allowed to cool to rt)
  10. customto give a pale beige solid (62 mg, 12%
  11. additiona mixture of diastereomers by NMR (8:2))
  12. custommp 197° C. (dec, preheat to 195° C.)

Sources & evidence

ORD record
ord-40ea756ae6024528b155a27b408ad635
Source dataset
uspto-grants-1995_12
Patent number
US05476933

Reaction notes

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