Phosphorus tribromide → HCID 86605565, compound

Participants

Reaction Steps

To a 0° C. solution of {4-[1-ethyl-1-(4-methyl-thiophen-2-yl)-propyl]-2-methyl-phenyl}-methanol (6 g,) in THF (50 ml) is treated with PBr3 (2.2 ml, 23.3 mmol) and warmed to RT. After stirring for 2 h, the mixture is partitioned between EtOAc and brine. The organic layer is MgSO4 dried, concentrated, and dissolved in anhydrous THF (30 ml) to give a solution of {4-[1-ethyl-1-(4-methyl-thiophen-2-yl)-propyl]-2-methyl-phenyl}-methane bromide. Separately, a solution of 3,3-dimethyl-butan-2-one (5.3 ml, 42.4 mmol) in THF (15 ml) is treated with LiHMDS (42.4 ml, 42.4 mmol, 1M in THF) at −70° C. for 1 h. This solution is transferred (via cannula) into a −70° C. solution of {4-[1-ethyl-1-(4-methyl-thiophen-2-yl)-propyl]-2-methyl-phenyl}-methanebromide/THF. The mixture is warmed to RT and stirred for 1 h. The reaction is diluted with EtOAc and washed with 0.2 N HCl until the aq layer is pH 2. The organic layer is concentrated to give the title compound (6.2 g, 79%).

Provenance & Evidence