1: 94 percent / toluene-p-sulfonic acid / toluene / Heating 2: 91 percent / diisobutylaluminium hydride / diethyl ether; hexane / 1) -40 deg C to room temperature, 2) room temperature, 12 h 3: 87 percent / N-bromosuccinimide, Me2S / CH2Cl2 / 5 h 4: 92 percent / m-chloroperbenzoic acid / CH2Cl2 / 12 h / 0 °C View Scheme

2: NaBH4 / methanol / Ambient temperature 3: toluene-p-sulfonic acid / toluene / 4 h / Heating 4: 96 percent / diisobutylaluminium hydride / diethyl ether; hexane / 1) -78 deg C to room temperature, 2) room temperature, 8 h View Scheme

toluene-4-sulfonic acid in toluene Heating;

1: 94 percent / toluene-p-sulfonic acid / toluene / Heating 2: 91 percent / diisobutylaluminium hydride / diethyl ether; hexane / 1) -40 deg C to room temperature, 2) room temperature, 12 h 3: 87 percent / N-bromosuccinimide, Me2S / CH2Cl2 / 5 h View Scheme

Yield given;

2: NaBH4 / methanol / Ambient temperature 3: toluene-p-sulfonic acid / toluene / 4 h / Heating 4: 96 percent / diisobutylaluminium hydride / diethyl ether; hexane / 1) -78 deg C to room temperature, 2) room temperature, 8 h 5: 91.3 percent / N-bromosuccinimide, Me2S / CH2Cl2 / 1) -30 deg C, 3 h, 2) room temperature, 1 h 6: 44.7 percent / m-chloroperbenzoic acid / CH2Cl2 / 1) 0 deg C, 1 h, 2) room temperature, 12 h 7: 33 percent / Bu3SnH, azoisobutyronitrile / benzene / 15 h / Heating View Scheme

2: NaBH4 / methanol / Ambient temperature 3: toluene-p-sulfonic acid / toluene / 4 h / Heating View Scheme

Multi-step reaction with 2 steps 1: 94 percent / toluene-p-sulfonic acid / toluene / Heating2: 91 percent / diisobutylaluminium hydride / diethyl ether; hexane / 1) -40 deg C to room temperature, 2) room temperature, 12 h