Enantioselective heterocyclic synthesis of spiro chromanone–thiochroman complexes catalyzed by a bifunctional indane catalyst
作者:Yaojun Gao、Qiao Ren、Hao Wu、Maoguo Li、Jian Wang
DOI:10.1039/c0cc03489d
日期:——
benzylidenechroman-4-ones and 2-mercaptobenzaldehydes for efficient construction of spiro chromanone-thiochroman complexes were accomplished with high yields and excellent selectivities via a novel bifunctional indane catalyst.
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 enantioselectivecascade 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
An efficient asymmetriccascadereaction catalyzed by a chiral bifunctional indane amine–thiourea catalyst has been developed. From a broad substrate scope, chiral dihydro-2H-pyran complexes that contained two stereogenic centers were obtained in a one-pot manner in good to excellent yields (72–97%) and high to excellent stereoselectivities (92–97% ee).