oily product 0 69 g yield 82 slowly crystallizes upon standing and can be recrystallized from n butanol n heptane mp 92 u00b0 c enantiomeric purity 98 1 h nmr 300 mhz cdcl 3 u03b4 1 03 d j 7 hz 3h 2 74 m 2h 2 97 m 3h 3 14 m 4h 3 42 t j 11hz 1h 3 57 dd j 11hz j 1 5hz 1h 4 35 sym m 4h 6 53 d j 7 9 hz 1h 6 61 d j 7 9 hz 1h 6 75 t j 7 9 hz 1h a free base of bis 2 chloroethyl amine is liberated by partitioning its hydrochloride salt between 5n aqueous sodium hydroxide and methylene chloride in an analogous manner to that used for example i the isolated bis 2 chloroethyl amine 0 94 g 6 56 mmol is then added in two portions over 1 hour into a stirred solution of s 2 methylsulfonyl oxy propionate 0 82 g 3 28 mmol in chlorobenzene 10 ml at room temperature the reaction mixture is stirred for additional 2 hours the solid precipitate is filtered off and washed with a small volume of chlorobenzene the filtrate is mixed with a solution of 2 3 dihydro 1 4 benzodioxin 1 4 benzodioxin 5 amine 0 46 g 3 mmol and the reaction mixture is heated to reflux for 18 hours after cooling the product is rendered basic with 5 aqueous sodium bicarbonate 20 ml and extracted twice with ether 50 ml the combined extracts are washed with water brine dried over magnesium sulfate and filtered the filtrate is concentrated in vacuo to give a crude product that can be directly.