Potassium Carbonate → (5-Chloro-2,3-dihydrobenzofuran-2-yl)methanol

To a solution of 4-chloro-2-(prop-2-en-1-yl)phenol (17 g, crude, nominally 101 mmol) in chloroform (100 ml) was added mCPBA (17.4 g, 101 mmol, 1 eq) with stirring for 1 h at 50° C. in an oil bath. Then the reaction mixture was concentrated under vacuum and re-dissolved in MeOH (100 ml). Potassium carbonate (27.6 g, 200 mmol, 2 eq) was added and the mixture was stirred for 5 hours at 50° C. The solids were filtered off and the filtrate was concentrated under vacuum. The crude material was purified by silica gel chromatography using 3% ethyl acetate in petroleum ether to elute. The product-containing fractions were combined and concentrated under vacuum to afford (5-chloro-2,3-dihydro-1-benzofuran-2-yl)methanol as yellow oil (6.15 g); 1H NMR (300 MHz, CDCl3): δ 7.00-7.18 (m, 2H), 6.80 (d, J=8.7 Hz, 1H), 4.88-4.97 (m, 1H), 3.85-3.90 (m, 1H), 3.70-3.79 (m, 1H), 3.19-3.27 (dd, J=9.3 Hz, 15.9 Hz, 1H), 2.98-3.05 (dd, J=7.5 Hz, 15.9 Hz, 1H), 2.10 (broad s, 1H).