Copper(II) Triflate-Catalyzed Intramolecular Hydroamination of Homoallylic Amino Alcohols as an Expedient Route to trans-2,5-Dihydro-1H-pyrroles and 1,2-Dihydroquinolines
作者:Weidong Rao、Prasath Kothandaraman、Chii Boon Koh、Philip Wai Hong Chan
DOI:10.1002/adsc.201000450
日期:2010.10.4
excellent yields up to 99% and with complete chemoselectivity. The mechanism is suggested to involve cop- per(II)-mediated dehydration of the homoallylic amino alcohol. Protonation of the resultant cop- per(II)-activated aminodiene is then thought to trigger subsequent intramolecular hydroamination to give the partially hydrogenated nitrogen heterocycle.
描述了一种新的高效合成路线,该路线依赖于温和且操作简便的条件下,三氟甲磺酸铜(II)催化均烯丙基氨基醇分子内胺化,生成反式-2,5-二氢-1 H-吡咯和1,2-二氢喹啉。对于反应导致的反式-2,5-二氢-1- ħ -吡咯产物,的52-83%的产率与沿反式选择性高达> 99:1个博士和EE值高达97%是从对映体富集完成1-(甲苯磺酰氨基)戊-4-烯-2-醇,ee范围为91–99%。不需要惰性和无湿气的条件,涉及1- [2-(甲苯磺酰基氨基)苯基] but-3-en-1-ols的反应可提供相应的1,2-二氢喹啉产物,收率高达99%,且完全的化学选择性。建议该机制涉及铜(II)介导的均烯丙基氨基醇的脱水。然后认为所得的经铜(II)活化的氨基二烯的质子化会触发随后的分子内加氢胺化反应,从而产生部分氢化的氮杂环。