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0 °C

To a suspension of sodium borohydride (1.52 g, 40 mmol) in ethanol (20 ml) at 0° C. was added a solution of 208 (6 g, 20 mmol) in THF (40 ml). The addition was over 20 min, the reaction mixture was stirred for 1 h at 0° C. and at rt for 30 min. 2M HCl (20 ml) was added (care—vigorous reaction!) and ethyl acetate (100 ml). The layers were separated and the aqueous layer was extracted with ethyl acetate (2×60 ml). The combined organic layers were washed with water (60 ml) and brine (60 ml), dried (MgSO4) and concentrated in vacuo to afford the crude material as an orange oil. Purification by flash column chromatography eluting with hex:EtOAc; 4:1 afforded the title compound (3.35 g, 55%) as a pale green solid. 1H NMR (270 MHz; CDCl3) 1.44 (3H, d, J=6.7 Hz, CH3), 2.87 (1H, dd, J=14.1, 6.9 Hz, one of CH2), 3.19 (1H, dd, J 14.1, 7.4 Hz, one of CH2), 3.85 (3H, s, OCH3), 4.65 (1H, sext, J=6.9 Hz, CH), 5.12 (2H, s, CH2Ph), 6.65-6.71 (2H, m, 2×CH), 6.81 (1H, d, J=8.2 Hz, CH), 7.25-7.43 (5H, m, 5×CH). 13C NMR (67.5 MHz; CDCl3) 18.71 (CH3), 40.80 (CH2), 56.08 (OCH3), 71.17 (CH2), 84.64 (CH), 112.0 (CH), 115.15 (CH), 121.93 (CH), 127.47 (CH), 127.87 (C), 128.0 (CH), 128.67 (CH), 136.99 (C), 148.14 (C), 149.13 (C), LC/MS (APCI−) tr=1.1 min, m/z 300.01 (M−H)−.

1. additionThe addition
2. customThe layers were separated
3. extractionthe aqueous layer was extracted with ethyl acetate (2×60 ml)
4. washThe combined organic layers were washed with water (60 ml) and brine (60 ml)
5. dry with materialdried (MgSO4)
6. concentrationconcentrated in vacuo
7. customto afford the crude material as an orange oil
8. customPurification by flash column chromatography
9. washeluting with hex