Cohalogenation of alkenes 6 by N-bromosuccinimide (NBS) in 3-methylpent-2-en-4-yn-1-ol provides β-bromo-3-methylpent-2-en-4-ynyl ether 7 precursors of 3-(penta-1,3,4-trienyloxy)cycloalkenes 9 which react chemo-and regio-selectively with NBS in methanol to give bromovinyl acetals10.
丙烯的卤化反应通过N-
溴琥珀
酰亚胺(
NBS)在3-甲基戊-2-烯-4-炔-1-醇中进行,生成β-
溴-3-甲基戊-2-烯-4-炔醚7,这是3-(五碳-1,3,4-烯氧基)环烯烃9的前体,它们在
甲醇中与
NBS发生选择性反应,产生
溴乙烯缩醛10。