Triphosgene → (2R,4S)-5-biphenyl-4-yl-4-isocyanato-2-methyl-pentanoic acid ethyl ester

HRID 2384025Notes

Reaction equation

HRID 2384025 reaction equation
Cl[C:2](Cl)([O:4]C(=O)OC(Cl)(Cl)Cl)Cl.Cl.[CH2:14]([O:16][C:17](=[O:36])[C@H:18]([CH3:35])[CH2:19][C@H:20]([NH2:34])[CH2:21][C:22]1[CH:27]=[CH:26][C:25]([C:28]2[CH:33]=[CH:32][CH:31]=[CH:30][CH:29]=2)=[CH:24][CH:23]=1)[CH3:15]>C(Cl)Cl>[CH2:14]([O:16][C:17](=[O:36])[C@H:18]([CH3:35])[CH2:19][C@H:20]([N:34]=[C:2]=[O:4])[CH2:21][C:22]1[CH:23]=[CH:24][C:25]([C:28]2[CH:33]=[CH:32][CH:31]=[CH:30][CH:29]=2)=[CH:26][CH:27]=1)[CH3:15]

Participants

4

Reactant 2

HCID 94429TriphosgeneHCID 25017086(2R,4S)-4-amino-5-(biphenyl-4-yl)-2-methylpentanoic acid ethyl ester hydrochloride

Product 1

HCID 86648207(2R,4S)-5-biphenyl-4-yl-4-isocyanato-2-methyl-pentanoic acid ethyl ester

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

To a vigorously stirred 1:1 mixture of methylene chloride/8% aqueous NaHCO3 (30 mL) at 0° C. is added triphosgene. After stirring the mixture at 0° C. for 5 minutes, (2R,4S)-4-amino-5-biphenyl-4-yl-2-methyl-pentanoic acid ethyl ester hydrochloride (400 mg, 1.15 mmol) is added and stirring is continued for 15 minutes. The organic phase is separated and dried over sodium sulfate. The solvent is removed under reduced pressure to furnish (2R,4S)-5-biphenyl-4-yl-4-isocyanato-2-methyl-pentanoic acid ethyl ester.

Workup

  1. stirringAfter stirring the mixture at 0° C. for 5 minutes
  2. stirringstirring
  3. customThe organic phase is separated
  4. dry with materialdried over sodium sulfate
  5. customThe solvent is removed under reduced pressure

Sources & evidence

ORD record
ord-070d4a0ce9d346d38a2f90d9a83fa84d
Source dataset
uspto-grants-2012_09
Patent number
US08263629B2

Reaction notes

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