To a solution of 4-(4-ethyl-1-methyl-1H-pyrazol-5-yl)-5-methyl-2-thiophenecarboxylic acid (137 mg, 0.55 mmol), 2-{(2S)-2-amino-3-[2-(trifluoromethyl)phenyl]propyl}-1H-isoindole-1,3(2H)-dione (211 mg, 0.55 mmol)[prepared in Preparation 6] and diisopropylethylamine (0.48 ml, 2.74 mmol) in Dichloromethane (5.47 ml) at 25° C. was added bromo-tris-pyrrolidino-phosphonium hexafluorophosphate (281 mg, 0.60 mmol) in one portion. The solution stirred at 25° C. for 1 h and was then partitioned between H2O-DCM. The aqueous phase was washed several times with DCM and the combined organic fractions were dried over Na2SO4, concentrated and purified via column chromatography (silica, 40-70% EtOAc in hexanes) yielding N-((1S)-2-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)-1-{[2-(trifluoromethyl)phenyl]methyl}ethyl)-4-(4-ethyl-1-methyl-1H-pyrazol-5-yl)-5-methyl-2-thiophenecarboxamide (262 mg, 0.45 mmol, 82% yield) as a clear oil: LCMS (ES) m/e 581 (M+H)+.
