反应详情

Et3N (400 uL, 2.87 mmol) and acetyl chloride (70 uL, 0.99 mmol) were added to a solution of 4-(azetidin-3-yloxy)-2,2-dimethyl-2,3-dihydro-benzofuran-6-carboxylic acid methyl ester (193c) (300 mg, 0.96 mmol) in CH2Cl2 (15 mL). The mixture was stirred at room temperature for 4 hr, then quenched with 1 N aqueous HCl (80 mL), and extracted with CH2Cl2 (80 mL). The organic layer was dried over MgSO4 and concentrated. The residue was purified by flash column chromatograph eluting with 80% EtOAc in hexanes to give a colorless oil (239 mg, 73% yield). 1H NMR (400 MHz, CDCl3) δ 7.12 (br. s., 1 H) 6.76 (br. s., 1 H) 5.03 (br. s., 1 H) 4.55 (br. s., 1 H) 4.43 (br. s., 1 H) 4.03-4.19 (m, 2 H) 3.89 (s, 3 H) 3.00 (s, 2 H) 1.92 (s, 3 H) 1.51 (br. s., 6 H).

1. customquenched with 1 N aqueous HCl (80 mL)
2. extractionextracted with CH2Cl2 (80 mL)
3. dry with materialThe organic layer was dried over MgSO4
4. concentrationconcentrated
5. customThe residue was purified by flash column chromatograph
6. washeluting with 80% EtOAc in hexanes