Lithium borohydride → 2-(4,5-Difluoro-2,3-dihydro-1H-inden-1-yl)ethanol

Participants

Reaction Steps

A mixture of E- and Z-(4,5-difluoro-indan-1-ylidene)-acetic acid ethyl ester (Intermediate TWENTY-3) (1.1 g) in EtOAc (25 mL) was hydrogenated with 10% Pd/C (0.16 g) under H2 (balloon) at rt for 16 h. The mixture was filtered through a bed of Celite® and the filtrate was evaporated under vacuum. The ester, (4,5-difluoro-indan-1-yl)-acetic acid ethyl ester (1.1 g, 4.58 mmol) in THF (60 mL) and MeOH (1 mL) was treated with LiBH4 (0.21 g, 8.5 mmol) at 65° C. for 5 h. The mixture was cooled and THF was removed under vacuum. The solution was diluted with EtOAc and sat. NH4Cl. The layers were separated and the organic layer was dried over MgSO4 and filtered. After evaporation, the alcohol, 2-(4,5-difluoro-indan-1-yl)-ethanol (Intermediate TWENTY-4) was isolated as a clear, colorless oil, 1.7 g, (88%). Use, 2-(4,5-difluoro-indan-1-yl)-ethanol (Intermediate TWENTY-4) in Method SEVENTEEN produced 4-(4,5-difluoro-indan-1-ylmethyl)-1,3-dihydro-imidazole-2-thione (Compound 156).

Provenance & Evidence