n-butyllithium in tetrahydrofuran byproducts: LiCl; a soln. of oct-1-yne in THF is cooled to -78°C and BuLi is slowly added with stirring, mixt. is stirred for 1 h, Bu3SnCl in THF is then added, mixt. is allowed to reach room temp. and stirred for a further hour; filtn. from LiCl;

1: With Schwartz's reagent in tetrahydrofuran T=20°C; 0.25 h; 2: With bromine in tetrahydrofuran; tetrachloromethane T=20°C; 0.333333 h; Further stages.;