1: 51 percent / 25 percent DIBAL-H / toluene / 4.5 h / -78 °C 2: 1.) 1.2 M n-BuLi / 1.) THF, hexane, -78 deg C, 1 h; 2.) THF, -78 deg C, 1.5 h; 3.) allowed to warm to r.t. during 1.5 h 3: 1.) 50 percent NaH / 1.) THF, -20 deg C, 30 min; 2.) -20 deg C, 30 min; 3.) r.t., 1 h View Scheme

1: 88 percent / pyridine / 1.) 0 deg C, 1 h; 2.) 25 deg C, overnight 2: 88 percent / P2O5 / CHCl3 / 12 h / Heating 3: 51 percent / 25 percent DIBAL-H / toluene / 4.5 h / -78 °C 4: 1.) 1.2 M n-BuLi / 1.) THF, hexane, -78 deg C, 1 h; 2.) THF, -78 deg C, 1.5 h; 3.) allowed to warm to r.t. during 1.5 h 5: 1.) 50 percent NaH / 1.) THF, -20 deg C, 30 min; 2.) -20 deg C, 30 min; 3.) r.t., 1 h View Scheme

1: 1.) 1.2 M n-BuLi / 1.) THF, hexane, -78 deg C, 1 h; 2.) THF, -78 deg C, 1.5 h; 3.) allowed to warm to r.t. during 1.5 h 2: 1.) 50 percent NaH / 1.) THF, -20 deg C, 30 min; 2.) -20 deg C, 30 min; 3.) r.t., 1 h View Scheme

sodium hydride 1.) THF, -20 deg C, 30 min; 2.) -20 deg C, 30 min; 3.) r.t., 1 h; Yield given. Multistep reaction;

(i) P2O5, CHCl3, (ii) iBu2AlH, toluene, (iii) /BRN= 4174060/, (iv) /BRN= 969135/, NaH; Multistep reaction;