Gold nanoparticles supported on TiO2 (∼1%) catalyse in high yields the selective cycloisomerisation of aryl propargyl ethers into the corresponding 2H-chromenes, under heterogeneous conditions. 2H,2′H-3,3′-Bichromenes resulting from a catalytic oxidative dimerization pathway are also formed as by-products.
在异构条件下,TiO2(∼1%)上支持的
金纳米粒子催化芳基
丙炔醚选择性环异构化成相应的
2H-色烯,产量很高。由催化氧化二聚化途径产生的 2H,2′H-3,3′-二氢苯也作为副产品生成。