水介质中糖基胺-酸对直接Aldol反应的协同催化研究

Glycosyl-tolysulfonyhydraine and Acid Catalyzed the Direct Aldol Reaction in Water

以Brnsted酸为催化剂,糖基对甲苯磺酰肼为助催化剂(胺),研究了芳香醛与酮在水介质中的直接Aldol反应。以对硝基苯甲醛和环己酮合成2-[羟基-(4-硝基苯基)]甲基环己酮为模型反应,考察了不同的酸、不同的糖基对甲苯磺酰肼、酸的用量、糖基对甲苯磺酰肼的用量、底物用量比r对模型反应的影响。在最佳反应条件(40 mol%乙酸为催化剂,30mol%葡萄糖基对甲苯磺酰肼为助催化剂(胺),水为溶剂,r=1∶5,于室温反应12 h)下,2-[羟基-(4-硝基苯基)]甲基环己酮的产率为93%。对反应底物进行扩展,结果表明,具有表面活性剂性质的葡萄糖基对甲苯磺酰肼与乙酸配合,能在水介质中有效地催化芳醛与环状酮的直接Aldol反应。

Direct Aldol reaction of aromatic aldehydes with ketone were investigated using Bronsted acid as the catalyst and glyco- syl-tolysulfonyhydraines as the cocatalyst in water. Effect of different catalyst and cocatalyst, HAc and glycosyl-tolysulfonyhyd- raines amount,substrates amount on aldol reaction were investigated by the reaction of 4-nitrobenzaldehyde with cyclohexanone to 2-[ hydroxy-（4-nitrophenyl） ] methylcyclohexanone. The yield of 2-[ hydroxy-（4-nitrophenyl） ] methylcyclohexanone was 93% un- der optimum reaction conditions [ HAc was 40 mol% , glycosyl-tolysulfonyhydraines was 30 mol% , r was 1 ： 5, at room temperature for 12 h]. Most acids can catalyze aldol reaction in water assisted by glycosyl-tolysulfonyhydraines. In comparison with surfactant assisted aldol reaction in water,the scope of substrates was improved.