1: 17 percent / pyridine / Ambient temperature 2: TsOH / tetrahydrofuran; CH2Cl2 / Ambient temperature 3: NaOH / tetrahydrofuran; H2O / 5 h / Ambient temperature 4: 1.) pyridine, 2.) aq.AcOH / 1.) CH2CH2, reflux, 15 h, 2.) pyridine, r.t., overnight 5: 1.) hydroquinone, 2.) KOH, 3.) TsOH / 1.) 140 deg C, 36 h, 2.) aq.MeOH, r.t., overnight, 3.) THF, r.t., overnight View Scheme

1: tetrahydrofuran / 1 h / 60 °C 2: 17.89 g / Et3N; tris(dibenzylideneacetone)dipalladium(0)*CHCl3; (1R,2R)-(+)-1,2-[NHC(O)(o-(PPh2)C6H4]2-cyclohexane / tetrahydrofuran / -50 - 20 °C 3: 98 percent / KOH / methanol / 2 h / 70 °C 4: 99 percent / K2CO3 / dimethylformamide / 20 °C 5: 98 percent / 2,6-lutidine / CH2Cl2 / 20 °C 6: 98 percent / Cl2(PCy3)2RuCHPh; ethylene; Pb(OAc)4 / CH2Cl2 / 14 h / 20 °C 7: tetrahydrofuran / 8 h / 0 - 55 °C 8: 2.19 g / aq. NaOH; aq. H2O2 / ethanol / 1 h / Heating 9: K2HPO4*3H2O; Na/Hg / methanol / 2 h / Heating 10: 2.35 g / aq. NaOH / CH2Cl2 / 1 h 11: 98 percent / Et3N / CH2Cl2 / 2 h / 0 - 20 °C 12: 95 percent / Pd(OAc)2; polymer-bound triphenylphosphine; Et3N / dimedone / tetrahydrofuran / 6 h / 20 - 50 °C 13: AD-mix-α; MeSO2NH2; H2O / 2-methyl-propan-2-ol / 168000 h / 3 - 6 °C 14: TBAF / tetrahydrofuran / 24 h / 20 °C 15: 291 mg / DMAP / CH2Cl2 / 20 °C 16: 96 percent / Amberlite IRA-401(OH) / methanol / 2 h / 20 °C View Scheme

(-)-10-CSA in toluene T=70°C; 30 h; Yield given. Yields of byproduct given;

1: Lipase PS 'amano’ IM / hexadeuterioacetone / 48 h / 25 °C / |Inert atmosphere 2: 1,1,1-triethoxyethane; hydroquinone / water / 36.75 h / 25 - 144 °C 3: sulfuric acid / 41 h / 29 - 79 °C 4: methanol / 25 - 65 °C View Scheme

chromium(VI) oxide

triethylamine in tetrahydrofuran 2.5 h; Ambient temperaturePancreatin as lipase;

1: 4-(N,N-dimethlyamino)pyridine; triethylamine / N,N-dimethyl-formamide / 16 h / 10 - 30 °C / Inert atmosphere 2: disodium hydrogenphosphate / water / 14 h / 25 - 30 °C / pH 7 / Enzymatic reaction View Scheme

pancreatin/base;

Pancreatin; triethylamine in tetrahydrofuran T=20°C; 3 h;

triethylamine in tetrahydrofuran 4 h; Ambient temperaturelipase from Mucor sp.;