Pyridine → 2-Carbomethoxy-5-tert-butyl-3-furyl isocyanate

HRID 1698905Notes

Reaction equation

HRID 1698905 reaction equation
[C:1](Cl)([Cl:3])=[O:2].[NH2:5][C:6]1[CH:10]=[C:9]([C:11]([CH3:14])([CH3:13])[CH3:12])[O:8][C:7]=1[C:15]([O:17][CH3:18])=[O:16].[N:19]1[CH:24]=[CH:23][CH:22]=[CH:21][CH:20]=1>C(Cl)Cl>[C:15]([C:7]1[O:8][C:9]([C:11]([CH3:14])([CH3:13])[CH3:12])=[CH:10][C:6]=1[N:5]=[C:1]=[O:2])([O:17][CH3:18])=[O:16].[ClH:3].[NH+:19]1[CH:24]=[CH:23][CH:22]=[CH:21][CH:20]=1

Participants

6

Reactant 3

HCID 1049PyridineHCID 6371PhosgeneHCID 18322376Methyl 3-amino-5-(tert-butyl)furan-2-carboxylate

Product 2

HCID 183223842-Carbomethoxy-5-tert-butyl-3-furyl isocyanateHCID 21584435Pyridinium hydrochloride

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent2×

Procedure

To a solution of phosgene (1.93M in toluene, 9.7 mL, 18.6 mmol, 3.0 equiv) in CH2Cl2 (80 mL) at 0° C. was added a solution of methyl 3-amino-5-tert-butylfuran-2-carboxylate (1.23 g, 6.2 mmol) and pyridine (1.97 g, 24.9 mmol, 4.0 equiv) in CH2Cl2 (20 mL). The reaction mixture was allowed to slowly warm to room temp. and rapidly form a precipitate. The resulting slurry was stirred at room temp. for 1 h, then concentrated under reduced pressure to give 2-carbomethoxy-5-tert-butyl-3-furyl isocyanate and pyridinium hydrochloride. 2-Carbomethoxy-5-tert-butyl-3-furyl isocyanate: 1H NMR (CDCl3) δ1.25 (s, 9H), 4.85 (s, 3H), 5.90 (s, 1H). The mixture was used in the next step without further purification.

Workup

  1. temperatureto slowly warm to room temp.
  2. customrapidly form a precipitate
  3. concentrationconcentrated under reduced pressure

Sources & evidence

ORD record
ord-4027bf23515b4fe291fd6fa24193eaca
Source dataset
uspto-grants-2002_02
Patent number
US06344476B1

Reaction notes

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