posted on 2010-08-20, 00:00authored byKe-Gong Ji, Hai-Tao Zhu, Fang Yang, Ali Shaukat, Xiao-Feng Xia, Yan-Fang Yang, Xue-Yuan Liu, Yong-Min Liang
Highly substituted dihalogenated dihydrofurans, dihydropyrroles, and dihydro-2H-pyrans bearing alkyl, vinyl, aryl, and heteroaryl moieties can be prepared in good to excellent yields (up to 99%) by allowing 1,4-butyne-diol, 4-aminobut-2-yn-1-ol, and pent-2-yne-1,5-diol derivatives to react with different electrophiles (I2, IBr, and ICl) at room temperature. Both halogen atoms generated from electrophiles were used effectively. The resulting halides can be further exploited by using palladium-catalyzed coupling reactions. The presence of trace amount of water is essential for this electrophilic cyclization.