triethylamine in diethyl ether; pentane under N2, dropwise addn. of CH3BBr2 in pentane into a mixture of diamine and triethylamine in diethyl ether at -78°C, warmed to room temp., boiled for 1 h under reflux; filtered (HNEt3Br), solvent distd. off;

n-butyllithium in diethyl ether; hexane byproducts: butane; under N2, diamine in petroleum ether and diethyl ether cooled to 0°C, dropwise addn. of n-BuLi in hexane, warmed to room temp. (evapn. of butane), cooled to -78°C, dropwise addn. of CH3BBr2 in petroleum ether, warmed to room temp.; solvent distd. off, condensed into a trap (-196°C) at 80°C;

in petroleum ether under N2, heated to boiling under reflux; solvent distd. off; elem. anal.;

amidosulfamic acid in pyridine 16 h; Heating;