in diethyl ether byproducts: propane, MgCl2; dry atmosphere; addn. of one equiv. of ethereal soln. of C3H7MgCl to Bu3SnH (0.125 mol); exothermic reaction; white soln. refluxed (2 h); addn. of immonium salt (0.1 mol); stirring for 2 h at room temp.; hydrolysis at 0 ° C;; extn. with ether, evapn., distn.,;