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Synfacts 2012; 8(8): 0913
DOI: 10.1055/s-0032-1316675
Polymer-Supported Synthesis
© Georg Thieme Verlag Stuttgart · New York

Asymmetric Michael Addition of Aldehydes to Nitroalkenes Using JH-CPP

Contributor(s):
Yasuhiro Uozumi
,
Hiroaki Tsuji
Wang CA, Zhang ZK, Yue T, Sun YL, Wang L, Wang WD, Zhang Y, Liu C, Wang W * Lanzhou University, P. R. of China
‘Bottom-Up’ Embedding of the Jørgensen–Hayashi Catalyst into a Chiral Porous Polymer for Highly Efficient Heterogeneous Asymmetric Organocatalysis.

Chem. Eur. J. 2012;
18: 6718-6723
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Further Information

Publication History

Publication Date:
19 July 2012 (online)

 
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Key words

Jørgensen–Hayashi catalyst - chiral porous polymers - Michael addition

Significance

A chiral porous polymer containing the Jørgensen–Hayashi catalyst (JH-CPP) was prepared by the Co2(CO)8-mediated trimerization of the ethynyl-modified Jørgensen–Hayashi catalyst 1 with tetra(4-ethynylphenyl)methane (2) in 98% yield. JH-CPP catalyzed the asymmetric ­Michael addition of aldehydes 4 to nitroalkenes 3 to give the corresponding adducts 5 in 67–99% yield with high stereoselectivity (10 examples).


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Comment

For the formation of 5b, JH-CPP was recovered by centrifugation and reused four times without loss of stereoselectivity, while the yield of 5b decreased from the third reuse (1st reuse: 94% yield, 98% ee, dr = 92:8; 3rd reuse: 51% yield, 97% ee, dr = 91:9; 4th reuse: 39% yield, 97% ee, dr = 88:12). JH-CPP was characterized by N2 adsorption, TGA, XRD, SEM, and 13C CP/MAS NMR spectroscopy.


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