solution is washed with 0 01n nahso 4 4 u00d7 to remove excess terbutylamine additioned with ethanol 2 ml and heated to reflux until disappearance of the pair of epoxides 3 4 the solvents are distilled under reduced pressure and the residue purified by flash chromatography to obtain the mixture of compounds 6 9 wherein r tert butyl 363 mg 72 ms m z calcd for c 27 h 35 f 2 no 3 459 3 found 460 4 m h opening of the epoxydes with dibenzylamine and selective deprotection of a benzyl a solution of the epoxydes 1 100 mg 0 51 mmol dibenzylamine 150 u03bcl 0 70 mmol in teramyl alcohol 1 ml is mixed at room temperature until disappearance of the rs sr epoxides then the crude product of the reaction is purified by flash chromatography obtaining 63 mg 63 of the amine mixture deriving from the opening of the rs sr epoxydes with dibenzylamine and 51 mg 65 of the pair of epoxides 4 5 the dibenzylamine mixture is dissolved in ethanol 5ml and hydrogenated with 5 pd c to obtain the benzylamines 2a 3a as main products 29 mg 74 opening of the epoxides with dibenzylamine and selective deprotection of a benzyl to a solution of the epoxides 1 5 g 25 7 mmol in teramyl alcohol 45 ml dibenzylamine 2 5 ml 13 0 mmol 0 5 eq was added and the mixture was stirred at room temperature until 5 of the rs sr epoxides was left then the crude product of the reaction was purified by flash chromatography obtaining 3 5 g 9 0 mmol 70 of the amine mixture deriving from the opening with dibenzylamine of.