A General Method for the Preparation of <i>N</i>-Sulfonyl Aldimines and Ketimines
作者:José Luis García Ruano、José Alemán、M. Belén Cid、Alejandro Parra
DOI:10.1021/ol048005e
日期:2005.1.1
[Reaction: see text] A simple procedure to obtain N-sulfonylimines involving the condensation of carbonyl compounds with p-tolyl or tert-butyl sulfinamides followed by oxidation with m-CPBA of the resulting N-sulfinylimines is reported. The method is applicable to aldehydes (aliphatics and aromatics) and ketones (diaryl, dialkyl, and aryl alkyl), even those containing enolizable protons. It also does
effective in dry DMF. The above-mentioned lithium acetate-catalyzed Mannich-type reaction between aldimines and various trimethylsilyl (TMS) enolethers such as silyl ketene acetal proceeded smoothly even in water-containing DMF. Then, Lewis base catalyzed three-component Mannich-type reactions of TMS enolether, tosylamide, and aromatic aldehyde having electron-withdrawing group such as p-nitrobenzaldehyde
Potassium or ammonium carboxylates catalyzed Mannich-type reaction between trimethylsilyl enolates and aldimines proceeded smoothly to afford the corresponding β-amino carbonyl compounds in good to high yields with high anti selectivity.
A highly efficient procedure for the preparation of N-sulfonylimines via condensation of sulfonamides with aldehydes as well as ketones in the presence of triarylmethyl chlorides as metal-free organo-catalysts at 40 °C is described. The advantages of this class of catalysts over the reported ones are their efficiency and possibility of running reactions in neutral media that makes them suitable for
Lithium benzamide- or potassium phthalimide-catalyzed Mannich-type reactionbetweentrimethylsilylenolates and aldimines proceeded smoothly in a DMF solvent to afford the corresponding β-amino esters in good to high yields.