Multi-step reaction with 8 steps
1: 1) n-BuLi / 1) THF, hexane, -70 deg C, 20 min, 2a) -70 deg C to RT, 2b) RT, 15 h
2: H2 / <(R)-(RuCl(p-cymene)BINAP>Cl / methanol; CH2Cl2 / 72 h / 50 °C / 37503 Torr
3: 97 percent / aq. HOAc / 3 h / 50 °C
4: 95 percent / tetramethylguanidine / tetrahydrofuran / 1) -70 to -30 deg C, 5 h, 2) -30 deg C, 2 d, 3) RT, 15 h
5: 85 percent / H2 / (R,R)-BF4 / methanol; CH2Cl2 / 48 h / 2250.2 Torr / Ambient temperature
6: 6M HCl / dioxane; CH2Cl2 / 0.5 h / Ambient temperature
7: hydroxybenzotriazole, N-ethyl-N'-(3-dimethylaminopropyl)carbodiimide*HCl / CH2Cl2 / 15 h / -10 deg C to RT
8: 4 percent / HOAc / H2O / 4 h / 50 °C
With
hydrogenchloride; n-butyllithium; 1,1,3,3-tetramethylguanidine; hydrogen; benzotriazol-1-ol; acetic acid; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride;
((+)-(1R)-[1,1'-binaphthalene]-2,2'-diylbis[diphenylphosphine-κP])chloro[(1,2,3,4,5,6-η)-1-methyl-4-(1-methylethyl)benzene]ruthenium(1+) chloride; (R,R)-+BF4-;
In
tetrahydrofuran; 1,4-dioxane; methanol; dichloromethane; water;
DOI:10.1055/s-1992-26351