the compound of formula ii was charged into a 1000 ml three necked round bottom flask equipped with a thermometer n 2 inlet and addition funnel 500 ml thf was charged to dissolve the 50 g of the compound formula ii at about 200 to 25 u00b0 c the batch was concentrated at 1 atm to a batch volume of about 150 ml the temperature was adjusted to about 200 to 25 u00b0 c 4 2 ml of lab pre formed r mecbs catalyst in toluene 3 mole was charged 70 4 ml of 1m borane thf complex in thf solution from aldrich chemical company milwaukee wis was slowly charged over 1 5 hrs at temperature between about 23 u00b0 and 28 u00b0 c the batch was sampled for hplc to monitor the progress of the reaction after the reaction was judged complete 20 ml of meoh was slowly charged to keep the temperature below 25 u00b0 c in order to quench the reaction the batch was concentrated under vacuum to afford a batch volume of about 100 ml at a temperature below 40 u00b0 c 250 ml of toluene and a solution of 5 ml sulfuric acid in 100 ml water was charged the mixture was agitated for about 10 min and the batch was allowed to.