New domino radical synthesis of aminoalcohols promoted by TiCl4–Zn/t-BuOOH system: selective hydroxyalkylation of amines in alcohol or in cyclic ether cosolvents
作者:Simona Prosperini、Nadia Pastori、Alessandra Ghilardi、Angelo Clerici、Carlo Punta
DOI:10.1039/c1ob05191a
日期:——
We report a new and fast domino synthesis of aminoalcohols under mild conditions. The free-radical reaction of aliphatic and aromatic amines with alcohol cosolvents is promoted by means of the TiCl4âZn/t-BuOOH system. According to the proposed mechanism, the amine reacts with two molecules of alcohol in an electrophilicânucleophilic cascade process. This procedure, if compared with the TiCl3/t-BuOOH-mediated protocol previously reported, appears to be more selective, of more general applicability and affords the desired products in higher yields. Besides, with the same catalytic system it was possible to promote the reaction of primary arylamines with two molecules of cyclic ether, leading to the formation of a wider range of functionalized aminoalcohols.
我们报告了一种在温和条件下快速合成氨基醇的新型多米诺反应。脂肪族和芳香族胺与醇共溶剂的自由基反应由TiCl4–Zn/t-BuOOH体系促进。根据提出的机理,胺与两个分子的醇反应,形成电亲核级联反应。如果与之前报道的TiCl3/t-BuOOH介导的方案相比,该过程显得更加选择性,适用性更广,并使目标产品的产率更高。此外,利用相同的催化体系,还可以促进初级芳胺与两个分子环醚的反应,从而形成更广泛种类的功能化氨基醇。