5 to 95 ch 3 cn in water containing 0 05 tfa over 10 min the retention times rt and the observed mass which corresponds to m h are listed in table 1 wherein u2014 ch r 1 r 3 and r 2 are as defined in the following table 1 to a cooled solution 0 u00b0 c of p fluoroacetophenone 13 8 g 0 1 mol and s 3 3 diphenyl 1 methyltetrahydro 3h pyrrolo 1 2 c 1 3 2 oxazaborole 30 ml of a 2m solution in toluene in anhydrous thf 400 ml under n 2 was added borane dimethylsulfide 14 ml 0 14 mol the solution was stirred at 0 u00b0 c for 30 min then ch 3 oh 50 ml was added followed by washing with 1 m hcl water saturated nahco 3 and drying over anhydrous na 2 so 4 the solvent was evaporated to give 13 5 g r p fluroro u03b1 methylbenzylalcohol anal data 1 h nmr cdcl 3 u03b4 7 35 d 2h u03b4 7 1 t 2h u03b4 4 9 q 1h u03b4 1 45 d 3h hplc chiralpak as column 10 isopropanol in hexane flow rate 1 ml min 5 68 min r isomer 98 6 10 min s isomer 2 to a cooled solution u2212 15 u00b0 c of the product of step 1 23 5 g 0 168 mol in toluene 300 ml was added diphenylphosporyl azide 55 4 g 0 395 mol followed by dbu 30 4 ml 0 2 mol after stirring overnight the resulting biphasic solution was poured into 500 ml 1.