2: 56 percent / 4-dimethylaminopyridine / CH2Cl2 / 21 h / 0 - 4 °C 3: 85 percent / tributyltin hydride, di-tert-butyl peroxide / 7.5 h / 50 °C 4: 86 percent / diisobutylaluminum hydride, 2,6-di-tert-butyl-4-methylphenol / toluene / -78 deg C to -20 deg C for 2h and then -20 deg C 1.7h 5: 96 percent / H2 / Lindlar / benzene; cyclohexane; cyclohexene / 13 h / 26 °C / 760 Torr 6: 100 percent 7: 95 percent / (n-C4H9)4NF / tetrahydrofuran / 3 h / 26 °C 8: 20percent NaOH-H2O / 18.3 h / 16 °C 9: Jones reagent / 0.33 h / -30 °C 10: CH3COOH / H2O; tetrahydrofuran / 16 deg C for 1h and 27 deg C for 29h View Scheme

Multistep reaction;

1: (1E)-iodo-(3S)-(tetrahydro-2H-pyran-2-yloxy)-1-octene With 1-pentynyl-copper; n-butyllithium; tris-(dimethylamino)-phosphine in diethyl ether; hexane T=-70°C; 0.5 h; 2: (R)-1-(3-(tert-butyldimethylsilyloxy)benzyl)-5-oxo-3-(tetrahydro-2H-pyran-2-yloxy)-cyclopentene in diethyl ether; hexane T=-70°C; 0.5 h;