Triphenyl phosphite → (S)-3-bromo-6a,7,8,9-tetrahydropyrido[3,2-e]pyrrolo[1,2-a]pyrazin-6(5H)-one

HRID 1645018Notes

Reaction equation

HRID 1645018 reaction equation
[Br:1][C:2]1[CH:3]=[C:4]([N+:18]([O-])=O)[C:5]([N:8]2[CH2:12][CH2:11][CH2:10][C@H:9]2[C:13](OCC)=[O:14])=[N:6][CH:7]=1.P(OC1C=CC=CC=1)(OC1C=CC=CC=1)OC1C=CC=CC=1>ClCCl.[NH4+].[O-][V](=O)=O.[Pt]>[Br:1][C:2]1[CH:7]=[N:6][C:5]2[N:8]3[CH2:12][CH2:11][CH2:10][C@H:9]3[C:13](=[O:14])[NH:18][C:4]=2[CH:3]=1

Participants

6

Reactant 2

HCID 7540Triphenyl phosphiteHCID 58324356(S)-ethyl 1-(5-bromo-3-nitropyridin-2-yl)pyrrolidine-2-carboxylate

Product 1

HCID 58324379(S)-3-bromo-6a,7,8,9-tetrahydropyrido[3,2-e]pyrrolo[1,2-a]pyrazin-6(5H)-oneYield 42.8%

Reagents, catalysts & solvents 3

HCID 23939PlatinumCatalystHCID 516859Ammonium metavanadateCatalystHCID 6344DichloromethaneSolvent

Procedure

(S)-ethyl 1-(5-bromo-3-nitropyridin-2-yl)pyrrolidine-2-carboxylate (8.6 g, 24.99 mmol) was dissolved in dichloromethane (Volume: 125 ml) and to this solution was added triphenyl phosphite (0.078 g, 0.250 mmol), ammonium metavanadate (0.175 g, 1.499 mmol) and Pt/C (5% wt.) (0.975 g, 0.250 mmol). The reaction mixture was hydrogenated at 80 psi at 25° C. for 4 h. The reaction mixture was filtered through celite using DCM and MeOH to complete the transfer and wash the celite plug. The combined filtrates and washes were concentrated in vacuo and crystallized with ethyl ether (75 mL). The precipitate was filtered and dried in vacuum to afford (S)-3-bromo-6a,7,8,9-tetrahydropyrido[3,2-e]pyrrolo[1,2-a]pyrazin-6(5H)-one (2.87 g, 10.70 mmol, 42.8% yield) as a pale beige solid. 1H NMR (400 MHz, DMSO-d6) δ ppm 1.82-2.03 (m, 3H) 2.11-2.26 (m, 1H) 3.27-3.47 (m, 1H) 3.49-3.63 (m, 1H) 4.01-4.11 (m, 1H) 7.06 (d, J=2.27 Hz, 1H) 7.77 (d, J=2.02 Hz, 1H) 10.57 (s, 1H). [M+H] calc'd for C10H10BrN3O, 268. found, 268.

Workup

  1. filtrationThe reaction mixture was filtered through celite
  2. washwash the celite plug
  3. concentrationThe combined filtrates and washes were concentrated in vacuo
  4. customcrystallized with ethyl ether (75 mL)
  5. filtrationThe precipitate was filtered
  6. customdried in vacuum

Sources & evidence

ORD record
ord-aef679c2eb54430693756e3415e92091
Source dataset
uspto-grants-2012_02
Patent number
US08124606B2

Reaction notes

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