A suspension of 3-(4-benzenesulfonyl-2-bromo-phenoxy)-propane 1-2-(R)-diol (0.390 g, 0.001 mol), Pd(OAc)2 (0.007 g, 0.00003 mol, 3 mol %), racemic-2-(di-t-butylphosphino)-1,1′-binaphthyl (0.012 g, 0.00003, 3 mol %) and K3PO4 (0.320 g, 0.0015, 1.5 equiv) in toluene (1 mL) was heated under argon atmosphere at 80° C. for 5 hours. After cooling to ambient temperature the mixture was diluted with ethyl acetate (1 mL), washed with water and saturated sodium chloride, dried (Na2SO4) and concentrated in vacuo. The crude material was purified by flash chromatography on silica gel (eluting with hexane-ethyl acetate; 1:1, v/v) to give (7-benzenesulfonyl-2,3-dihydro-benzo[1,4]dioxin-2(R)-yl)-methanol as an oil which solidified upon standing. (0.160 g; 52%). m. p. 112.0-113.5° C., [α]=+36.7° (CHCl3, c=1).
