Multi-step reaction with 9 steps
1: 1.) TiCl4 / 1.) CH2Cl2, -78 deg C, 20 min, 2.) to -50 deg C, 2 h
2: 1.) lithium diisopropylamide, 2.) hexamethylphosphoramide / 1.a) THF, -78 to -10 deg C, 30 min, b) -10 deg C, 1 h, 2.) -78 deg C, 1 h
3: 90 percent / dimethylaminopyridine / toluene / 16 h / Heating
4: 25 percent / trifluoroacetic anhydride / 1.) -70 deg C, 1,5 h, 2.) to 25 deg C, 2 h, 3.) 25 deg C, 65 h
5: 1.) ozone, 2.) PPh3 / 1.) CH2Cl2, -70 deg C, 2.) to 25 deg C, 12 h
6: 1.) TiCl4 / 1.) CH2Cl2, -70 deg C, 20 min, 2.) -70 to -50 deg C, 1 h
7: 75 percent / acetonitrile; acetone / 0.42 h / Irradiation
8: 82 percent / KOH / 12 h / 25 °C
9: 56 percent / dipyridylcarbonate, dimethylaminopyridine / toluene / 16 h / 70 °C
With
N,N,N,N,N,N-hexamethylphosphoric triamide; dmap; potassium hydroxide; 2,2'-dipyridyl carbonate; titanium tetrachloride; ozone; triphenylphosphine; trifluoroacetic anhydride; lithium diisopropyl amide;
In
acetone; toluene; acetonitrile;
DOI:10.1016/S0040-4020(01)91213-X