HCID 11010979, compound → HCID 18393302, compound

Temperature

0 °C

As reported by Schinzer et al.104, a solution of lithium aluminum hydride (8.4 ml of 1.0M solution in THF, 8.4 mmol, 1.5 equiv) was added dropwise to a solution of compound 74 (1.5 g, 5.62 mmol, 1 equiv) in ether (40 ml) at 0° C. The reaction mixture was stirred at 0° C. for 30 min before it was warmed to room temperature and stirred for an additional 10 h. The reaction mixture was cooled again to 0° C. and excess hydride was quenched by dropwise addition of water (0.32 ml), 15% aqueous sodium hydroxide (0.32 ml), and water (1 ml). Anhydrous sodium sulfate was added, and the resulting suspension was stirred at room temperature for 4 h. The white precipitate formed was filtered through a plug of celite and washed with ether. The filtrate and washings were concentrated in vacuo to give a crude oil that was purified by flash column chromatography (15% EtOAc/hexanes) to give alcohol 75 (0.772 g, 97%) as a colorless oil. The column was eluted with ethyl acetate to recover the chiral auxiliary: [α]22D=−10.3 (c=0.8, CHCl3); TLC Rf=0.39 (silica gel, 25% EtOAc/hexanes); 1H NMR (600 MHz, CDCl3) δ 4.670 (s, 1H), 4.64 (s, 1H), 3.50-3.46 (m, 1H), 3.41-3.37 (m, 1H), 2.02-1.92 (ni, 2H), 1.685 (s, 3H), 1.65-1.34 (m, 4H), 1.12-1.04 (m, 1H), 0.909-0.89 (d, 3J=6.6 Hz, 3H); 13C NMR (100 MHz, CDCl3) δ 146.224, 110.011, 68.538, 38.237, 35.898, 32.948, 25.146, 22.576, 16.787.

1. temperaturewas warmed to room temperature
2. stirringstirred for an additional 10 h
3. temperatureThe reaction mixture was cooled again to 0° C.
4. customexcess hydride was quenched by dropwise addition of water (0.32 ml), 15% aqueous sodium hydroxide (0.32 ml), and water (1 ml)
5. additionAnhydrous sodium sulfate was added
6. stirringthe resulting suspension was stirred at room temperature for 4 h
7. customThe white precipitate formed
8. filtrationwas filtered through a plug of celite
9. washwashed with ether
10. concentrationThe filtrate and washings were concentrated in vacuo
11. customto give a crude oil that
12. customwas purified by flash column chromatography (15% EtOAc/hexanes)

ORD record

ord-5a1936d914144d37926259066a6e1dd7

Source dataset

uspto-grants-2011_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07893268B2