微反应器控制的化学反应的选择性

研究利用分子筛、Nafion薄膜、低密度聚乙烯薄膜和囊泡作为微反应器控制有机光化学反应的方向,提高反应的选择性和可能性.在NaY沸石或低密度聚乙烯薄膜中,带有长烷基链或醚链的二芳基化合物光二聚只生成分子内的加成产物,而不生成分子间的加成产物,从而在底物浓度很大的情况下,高选择性地合成了大环化合物.通过控制底物和敏化剂分子在ZSM-5沸石、Nafion薄膜和囊泡中的分布高选择性地控制烯烃光敏氧化反应的方向,单一地生成单重态氧的氧化产物或超氧负离子的氧化产物.利用Nafion薄膜作为介质进行光诱导电子转移,得到超长寿命的电荷分离态.

MICROREACTOR-CONTROLLED SELECTIVITY IN ORGANIC PHOTOCHEMICAL REACTIONS

Molecular sieves zeolites, Nafion membranes, low density polyethylene films and mixed surfactant vesicles have been used as microreactors to control the product selectivity in organic photochemical reactions. The photocycloadditions of diaryl compounds with long flexible chains included in NaY zeolite or low density polyethylene films yield intramolecular photocyclomers to the exclusion of intermolecular products. The photosensitized oxidation of alkenes included in pentasil zeolite or Nafion membrane or vesicles can be directed selectively towards either the singlet oxygen mediated or the superoxide radical anion mediated products by controlling the status and location of the substrate and sensitizer molecules in the reaction media. Long lived photoinduced charge separation in Ru(bpy) 3 2+ /viologen system at Nafion membrane solution interface was achieved.