Insoluble Polymer‐Supported Conjugate Bases of Thiazolium Ions As Catalysts in Organic Chemistry

AbstractThe synthetic possibilities of the generalized benzoin condensation are examined: benzoin condensation in its strict sense and closely related reactions, Michael type additions of aldehydes to activated double bonds, and oxidative benzoin condensation. In solid phase chemistry, comments are made on cyanide resins and details are given on the preparation of insoluble 5‐(2‐hydroxyethyl)‐4‐methyl‐3‐(polystyrylmethyl)thiazolium chloride and of 4‐methyl‐3‐(polystyrylmethyl)thiazolium chloride. Examples of the use of polymer thiazolium salts in the three types of reactions mentioned are presented and information on the stability of these salts is presented.