A.Elimination of dihalides Colle C 2 equiv B C三C strong HH H X (E2) vicinal geminal dihalide dihalide 1 equiv. of base C三C HH easier more difficult NaNH2 KOH,200C BuOK NaNH2,150C KOHCollege A. Elimination of dihalides of Science C X H C X H C H H C X X or 2 e quiv. st r o n g B (E 2 ) C C vi c ina l diha l i d e ge m ina l diha l i d e C X H C X H C C C X C H 1 equiv. of base 1 equiv. of base easier NaNH 2 tBuOK KOH more difficult KOH, 200ºC NaNH 2, 150ºC