Asymmetric Mannich Reaction of Malonates with Aldimines Using Yb<sup>III</sup>-Pybox Complexes Supported on Self-Assembled Organic-Inorganic Hybrid Silica with an Imidazolium Framework
作者:Babak Karimi、Ehsan Jafari、Dieter Enders
DOI:10.1002/ejoc.201402713
日期:2014.11
and recyclable catalyst in the enantioselective Mannich reaction of malonateesters with N-Boc aldimines to afford the corresponding products in good yields and enantioselectivities. In particular, it has been shown that the use of catalyst A resulted in much superior enantioselectivities in comparison with either 1:2 Yb(OTf)3/3b on a periodicmesoporousorganosilica with 10 percent imidazolium framework
A chiral calcium complex was found to be effective for the Mannich reactions of malonates with N-Boc imines. The desired adducts were obtained in excellent yields (up to 95%) with moderate to good enantioselectivities (up to 77% ee).