(+-)-trans4-Methylene-2-phenylcyclopentanoic acid → (+-)-trans-1-Hydroxymethyl-4-methylene-2-phenylcyclopentane
Reaction equation
[CH2:1]=[C:2]1[CH2:6][C@@H:5]([C:7](O)=[O:8])[C@H:4]([C:10]2[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=2)[CH2:3]1.[H-].[Al+3].[Li+].[H-].[H-].[H-]>C1COCC1>[OH:8][CH2:7][C@@H:5]1[CH2:6][C:2](=[CH2:1])[CH2:3][C@H:4]1[C:10]1[CH:11]=[CH:12][CH:13]=[CH:14][CH:15]=1Participants
4
Procedure
To a solution of (+−)-trans-4-methylene-2-phenylcyclopentanoic acid (26 g, 129 mmol) from Step A in THF (600 mL) under nitrogen at −10° C. was added dropwise over 15 min 1M lithium aluminum hydride (LAH) in THF (193 mL, 193 mmol). After 16 h at rt, the excess LAH was quenched by dropwise addition of acetone and the reaction was then poured into dilute aq. HCl. The mixture was extracted twice with ether and the organic layers were washed with brine, dried over sodium sulfate, combined and concentrated. The residue was purified by FC (20% ethyl acetate in hexanes) to afford the title product (23.8 g) as an oil.