1: 92 percent / 20percent H2SO4, SiO2 / CHCl3 / 6 h 2: 20 percent / hexane / 6 h / Ambient temperature; Irradiation 3: 100 percent / H2SO4 / acetic acid / 0.5 h / Heating View Scheme

Multi-step reaction with 2 steps 1: 92 percent / 20percent H2SO4, SiO2 / CHCl3 / 6 h2: 20 percent / hexane / 6 h / Ambient temperature; Irradiation  

 in  hexane 6 h;  Ambient temperatureIrradiation;   

With  sulfuric acid; silica gel in  chloroform 6 h;