Triethylamine → tert-butyl 4-[(1S)-2-methoxy-1-(4-nitrobenzyl)-2-oxoethyl]piperazine-1-carboxylate

HRID 1519560Notes

Reaction equation

HRID 1519560 reaction equation
[CH2:1]([N:4]([CH2:12][CH:13]=C)[C:5](=[O:11])[O:6][C:7]([CH3:10])([CH3:9])[CH3:8])[CH:2]=C.O=[O+][O-].Cl.[NH2:19][C@@H:20]([CH2:25][C:26]1[CH:31]=[CH:30][C:29]([N+:32]([O-:34])=[O:33])=[CH:28][CH:27]=1)[C:21]([O:23][CH3:24])=[O:22].C(N(CC)CC)C.[BH-](OC(C)=O)(OC(C)=O)OC(C)=O.[Na+]>C(Cl)Cl.O>[CH3:24][O:23][C:21](=[O:22])[C@@H:20]([N:19]1[CH2:2][CH2:1][N:4]([C:5]([O:6][C:7]([CH3:8])([CH3:9])[CH3:10])=[O:11])[CH2:12][CH2:13]1)[CH2:25][C:26]1[CH:27]=[CH:28][C:29]([N+:32]([O-:34])=[O:33])=[CH:30][CH:31]=1

Participants

8

Reactant 5

HCID 8471TriethylamineHCID 24823OzoneHCID 5049666Sodium triacetoxyborohydrideHCID 5107724tert-Butyl N,N-diallylcarbamateHCID 11715866Methyl 4-nitro-L-phenylalaninate hydrochloride

Product 1

HCID 118202423tert-butyl 4-[(1S)-2-methoxy-1-(4-nitrobenzyl)-2-oxoethyl]piperazine-1-carboxylate

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 6344DichloromethaneSolvent

Procedure

To a cooled solution of tert-butyl diallylcarbamate (145 mg, 0.74 mmol) in DCM (15 mL) at −78° C. was bubbled ozone for about 5 minutes. The solution was light blue at that point. Excess ozone was removed by flushing nitrogen through the reaction. To the reaction was added methyl(2S)-2-amino-3-(4-nitrophenyl)propanoate hydrochloride and triethylamine (74 mg, 0.74 mmol), followed by NaB(OAc)3H (940 mg, 4.4 mmol). The reaction was allowed to warm to RT, and stir for an additional 4 hours. The mixture was poured into water, extracted with DCM. The organic layer was washed with brine, dried with MgSO4, and purified by prep-TLC (50% EtOAc and Hexanes) to afford 93 mg of the desired tert-butyl 4-[(1S)-2-methoxy-1-(4-nitrobenzyl)-2-oxoethyl]piperazine-1-carboxylate. LC-MS (IE, m/z): 394 [M+1]+.

Workup

  1. customExcess ozone was removed
  2. customby flushing nitrogen
  3. customthrough the reaction
  4. extractionextracted with DCM
  5. washThe organic layer was washed with brine
  6. dry with materialdried with MgSO4
  7. custompurified by prep-TLC (50% EtOAc and Hexanes)

Sources & evidence

ORD record
ord-e6ed412a56c54ab3a5a1003df8a5eab3
Source dataset
uspto-grants-2015_07
Patent number
US09073882B2

Reaction notes

Loading…