Ethyl 3-(trimethylsilyl)propynoate → 1-(2,6-Difluorophenyl)-1-[6-(2,4-difluorophenyl)-5-(hydroxymethyl)pyridin-2-yl]but-3-yn-2-one

Participants

Reaction Conditions

Reaction Steps

To a solution of 3-({[tert-butyl(dimethyl)silyl]oxy}methyl)-6-(2,6-difluorobenzyl)-2-(2,4-difluorophenyl)pyridine (from Step D above, 4.63 g) in THF was added lithium bis(trimethylsilyl)amide (22.0 mL, 1.0 M in THF) at −78° C. After stirring ½ h at −78° C., ethyl 3-(trimethylsilyl)prop-2-ynoate (2.2 mL) was added. The mixture was warmed to 0° C. and stirred for a couple of hours until reaction complete. The reaction was quenched with 0.1 N HCl, and extracted with ethyl acetate. The organic layer was washed with brine, dried over MgSO4 and concentrated. The residue in THF was added TBAF (25 mL, 1N in THF) at 0° C. and stirred for 1 h. The solution was washed with water, brine, dried over MgSO4 and concentrated. The residue was purified by silica gel (100% methylene chloride) to give title compound (1.08 g).

Provenance & Evidence