2: 95 percent / diisobutylaluminium hydride / CH2Cl2 3: DMAP, Et3N / CH2Cl2 / 0.5 h / 0 °C 4: LiCl / dimethylformamide / 0.5 h / 0 °C 6: O2, rose bengal / CH2Cl2; methanol / -78 °C / Irradiation 7: 2N hydrochloric acid / tetrahydrofuran / 2 h / Ambient temperature 8: Irradiation View Scheme

Multi-step reaction with 7 steps 2: 95 percent / diisobutylaluminium hydride / CH2Cl2 3: DMAP, Et3N / CH2Cl2 / 0.5 h / 0 °C4: LiCl / dimethylformamide / 0.5 h / 0 °C6: O2, rose bengal / CH2Cl2; methanol / -78 °C / Irradiation7: 2N hydrochloric acid / tetrahydrofuran / 2 h / Ambient temperature  

Multi-step reaction with 4 steps 2: 95 percent / diisobutylaluminium hydride / CH2Cl2 3: DMAP, Et3N / CH2Cl2 / 0.5 h / 0 °C4: LiCl / dimethylformamide / 0.5 h / 0 °C