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Article proline and hydroxyproline as the raw materials, design , synthesis of a bifunctional catalyst of the series having a sulfonamide and thiourea structure , synthesis of a series of α-position substituent nitro ethylenically obtained is then double functional catalyst for the catalytic aldehyde with an α-position substituent nitro alkylene asymmetric Michael addition reaction, the are screened better hydroxyproline derivative 2 - trifluoromethanesulfonamide -4 - hydroxy silyl ether catalyst 29. Effects of solvent , reaction temperature , amount of catalyst , additives and other factors on the reactivity and selectivity , the optimum conditions to obtain a reaction as follows : The reaction temperature is 0 ° C , DMF as solvent , 5 mol% p-nitrobenzoic acid as an additive , 5 mol% amount of catalyst . The reaction was carried out to a yield of more than 80% can be obtained in this condition, the values of up to 95% ee , and greater than 19:1 DR value .
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