Unique site-selectivity control in asymmetric Michael addition of azlactone to alkenyl dienyl ketones enabled by P-spiro chiral iminophosphorane catalysis
作者:Ken Yoshioka、Kohei Yamada、Daisuke Uraguchi、Takashi Ooi
DOI:10.1039/c7cc01715d
日期:——
and enantioselective 1,6-addition of azlactone to various alkenyl dienyl ketones has been achieved under P-spiro chiral triaminoiminophosphorane catalysis. This site-selectivity control relies on the distinct ability of the conjugate acids of iminophosphoranes, aminophosphonium ions, to precisely differentiate between the three electrophilic reaction sites of alkenyl dienyl ketones, which is further demonstrated
在P-螺环手性三氨基亚氨基正膦催化下,将内酯向多种烯基二烯基酮进行高度区域,非对映和对映选择性的1,6-加成反应。这种位点选择性控制依赖于亚氨基正膦酸酯,氨基离子的共轭酸在烯基二烯基酮的三个亲电反应位点之间精确区分的独特能力,这进一步通过区分性不对称的1,6-添加add内酯来证明。二烯基酮,保留完整存在的烯基酮。