反应详情

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%).

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)