Proton sponge → 1-(Isocyanatomethyl)-4-(propan-2-yloxy)benzene

HRID 852287

Reaction equation

HRID 852287 reaction equation
CN(C)[C:3]1[C:12]2[C:7](=CC=C[C:11]=2[N:13]([CH3:15])C)[CH:6]=[CH:5][CH:4]=1.[CH:17]([O:20]C1C=CC(CC(O)=O)=CC=1)([CH3:19])[CH3:18].C1(P(N=[N+]=[N-])(C2C=CC=CC=2)=[O:38])C=CC=CC=1>O1CCCC1>[N:13]([CH2:11][C:12]1[CH:3]=[CH:4][C:5]([O:20][CH:17]([CH3:19])[CH3:18])=[CH:6][CH:7]=1)=[C:15]=[O:38]

Participants

5

Procedure

1,8-Bis(dimethylamino)-naphtalene (3.19 g, 14.9 mmol) was added to a solution of 4-(isopropoxy)phenyl acetic acid (2.89 g, 14.9 mmol) in dry tetrahydrofuran (18 mL) at rt under argon atmosphere. After 25 minutes stirring at rt diphenylphosphoryl azide (4.10 g, 14.9 mmol) was added dropwise and the mixture refluxed for 6 hours. It was allowed to cool to rt and then stored at −20° C. overnight to precipitate out the ammonium phosphate salt. A mixture of diethyl ether and ethyl acetate (1:1 v/v, 25 mL) was added to the cold reaction mixture. The precipitate was filtered from the reaction mixture and washed with diethyl ether:ethyl acetate (1:1 v/v, 20 mL). The filtrate was evaporated to dryness giving 1-isocyanatomethyl-4-isopropoxybenzene as an oil (3.2 g), which was used in the next step without further purification.

Workup

  1. additionwas added dropwise
  2. temperaturethe mixture refluxed for 6 hours
  3. customto precipitate out the ammonium phosphate salt
  4. additionA mixture of diethyl ether and ethyl acetate (1:1 v/v, 25 mL)
  5. additionwas added to the cold reaction mixture
  6. filtrationThe precipitate was filtered from the reaction mixture
  7. washwashed with diethyl ether:ethyl acetate (1:1 v/v, 20 mL)
  8. customThe filtrate was evaporated to dryness

Sources & evidence

ORD record
ord-64e9399581e34879b902cfad5fac08f1
Source dataset
uspto-grants-2007_08
Patent number
US07253186B2

Linked notes

Loading…