可见光促进芳香醛的绿色合成

On green synthesis of aromatic aldehydes promoted by visible light

芳香醛类化合物是一种重要的化工原料,广泛应用于医药、农药、香料和染料等行业,因而高效制备芳香醛对化工行业非常关键.然而,传统的芳香醛合成方法因使用高毒性催化剂并产生大量有毒副产物,对环境污染严重,从而限制了其应用.为此,设计了可见光促进的氧气氧化溴化苄和氯化苄的反应.通过对反应条件的筛选,确定了最佳反应条件.当使用fac-Ir(ppy)_(3)作为光催化剂,碳酸钾作为碱,乙腈作为溶剂时,该催化体系表现出优异的催化活性,各类取代基的溴化苄和氯化苄底物均可转化为相应的芳香醛,最高可以达到96%的收率.

Aromatic aldehydes are widely used in the pharmaceutical,pesticide,fragrance,and dye industries as a key chemical raw materials.Therefore,the efficient preparation of aromatic aldehydes is crucial to the chemical industry.However,the traditional synthesis of aromatic aldehydes is limited in application due to the use of toxic catalysts and the generation of toxic by-products.To this end,a reaction for the visible light-promoted oxidation of benzyl bromide and benzyl chloride with oxygen was designed.The optimum reaction conditions were determined by screening.Using fac-Ir(ppy)_(3) as photocatalyst,potassium carbonate was used as alkali and acetonitrile was used as solvent,the catalytic system showed excellent catalytic activity.Benzyl bromide substrates containing various substituents could be converted into corresponding aromatic aldehydes,with the highest yield of 96%.