Enantioselective Synthesis of Densely Functionalized Pyranochromenes via an Unpredictable Cascade Michael-Oxa-Michael-Tautomerization Sequence
作者:Qiao Ren、Yaojun Gao、Jian Wang
DOI:10.1002/chem.201002490
日期:2010.12.10
A surprising example of enantioselective cascade Michael–oxa‐Michael–tautomerization reactions of malononitrile and benzylidenechromanones has been developed. In this case, malononitrile functions as both nucleophile and electrophile. Meanwhile, a simple bifunctional indane amine–thiourea catalyst has been discovered to promote this process to afford high yields (up to 99%) and high to excellent enantiomeric
已经开发出令人惊讶的丙二腈和亚苄基苯并二氢呋喃酮的对映选择性级联迈克尔-氧杂-迈克尔-互变异构反应的例子。在这种情况下,丙二腈同时具有亲核试剂和亲电子试剂的功能。同时,已经发现一种简单的双功能茚满胺-硫脲催化剂可以促进这一过程,从而提供高收率(高达99%)和高到极好的对映体过量(81-99%ee)。