tert-Butanol → (2,2-Dimethyl-2,3-dihydro-benzofuran-7-yl)-carbamic acid tert-butyl ester

HRID 1373633Notes

Reaction equation

HRID 1373633 reaction equation
[CH3:1][C:2]1([CH3:14])[CH2:6][C:5]2[CH:7]=[CH:8][CH:9]=[C:10](C(O)=O)[C:4]=2[O:3]1.CC[N:17]([CH2:20]C)CC.C1C=CC(P(N=[N+]=[N-])(C2C=CC=CC=2)=[O:29])=CC=1.[C:39]([OH:43])([CH3:42])([CH3:41])[CH3:40]>>[C:39]([O:43][C:20](=[O:29])[NH:17][C:10]1[C:4]2[O:3][C:2]([CH3:1])([CH3:14])[CH2:6][C:5]=2[CH:7]=[CH:8][CH:9]=1)([CH3:42])([CH3:41])[CH3:40]

Participants

5

Reactant 4

HCID 6386tert-ButanolHCID 8471TriethylamineHCID 199401P,P-Diphenylphosphinic azideHCID 27954692,2-Dimethyl-2,3-dihydro-1-benzofuran-7-carboxylic acid

Product 1

HCID 69419090(2,2-Dimethyl-2,3-dihydro-benzofuran-7-yl)-carbamic acid tert-butyl esterYield 75%

Procedure

A first intermediate compound 2,2-Dimethyl-2,3-dihydro-benzofuran-7-ylamine, was produced as follows: To a mixture of 2,2-dimethyl-2,3-dihydro-benzofuran-7-carboxylic acid (Maybridge, 6.15 g, 32.0 mmol) in dry tert-butanol (100 mL) was added Et3N (8.9 mL, 64.0 mmol) and the mixture became homogenous. DPPA (8.3 mL, 38.4 mmol) was added and the reaction was refluxed overnight. The reaction was concentrated and diluted with EtOAc. The organics were washed with water (2×) and brine, dried over Na2SO4 and concentrated. Purification by SiO2 chromatography (AnaLogix RS-120, 2–25% EtOAc/Hex) gave (2,2-dimethyl-2,3-dihydro-benzofuran-7-yl)-carbamic acid tert-butyl ester as a clear oil (6.33 g, 24.0 mmol, 75%).

Workup

  1. temperaturethe reaction was refluxed overnight
  2. concentrationThe reaction was concentrated
  3. additiondiluted with EtOAc
  4. washThe organics were washed with water (2×) and brine
  5. dry with materialdried over Na2SO4
  6. concentrationconcentrated
  7. customPurification by SiO2 chromatography (AnaLogix RS-120, 2–25% EtOAc/Hex)

Sources & evidence

ORD record
ord-2738ba7e8f8e49868092cfcf32cb384d
Source dataset
uspto-grants-2007_01
Patent number
US07160888B2

Reaction notes

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