system 4h j ab 13 7 hz 7 25 m 15h and 9 72 s 1h hrms calcd for m 1 c 23 h 24 no 330 450 found 330 1836 anal calcd for c 23 h 23 on c 83 86 h 7 04 n 4 25 found c 83 64 h 7 42 n 4 19 hplc on chiral stationary phase s s pirkle whelk o 1 column 250 u00d7 4 6 mm i d mobile phase hexane isopropanol 99 5 0 5 v v flow rate 1 5 ml min detection with uv detector at 210 nm retention time of the desired s isomer 8 75 min retention time of the r enantiomer 10 62 min a solution of oxalyl chloride 8 4 ml 0 096 mol in dichloromethane 240 ml was cooled to 74 u00b0 c a solution of dmso 12 0 ml 0 155 mol in dichloromethane 50 ml was then slowly added at a rate to maintain the temperature at 74 u00b0 c addition time u02dc 1 25 hr the mixture was stirred for 5 min followed by addition of a solution of u03b2s 2 bis phenylmethyl amino benzene propanol 0 074 mol in 100 ml of dichloromethane addition time 20 min temp 75 u00b0 c to.