Zn-proline catalyzed direct aldol reaction in aqueous media.
نویسندگان
چکیده
Zn complexes of proline, lysine and arginine are efficient catalysts for the aldol addition of p-nitrobenzaldehyde and acetone in aqueous medium, giving quantitative yields and enantiomeric excesses up to 56% with 5 mol% of the catalysts at room temperature.
منابع مشابه
Dual mechanism of zinc-proline catalyzed aldol reactions in water.
The aldol reaction of acetone with aldehydes in aqueous medium under catalysis by zinc-proline (Zn(L-Pro)2) and secondary amines such as proline, (2S,4R)-4-hydroxyproline (Hyp) and (S)-(+)-1-(2-pyrrolidinomethyl)pyrrolidine (PMP) is shown to proceed by an enamine mechanism, as evidenced by reductive trapping of the iminium intermediate, while the aldol reaction of dihydroxyacetone (DHA) under c...
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The aldol reaction catalyzed by L-proline has been monitored and the accepted mechanism confirmed by intercepting and characterizing, for the first time, all the proposed intermediates by ESI-MS/MS.
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ورودعنوان ژورنال:
- Chemical communications
دوره 9 شماره
صفحات -
تاریخ انتشار 2003