Triphenylphosphine → (S)-ethyl 2-(7-(4-(allyloxy)-4-methylpiperidin-1-yl)-2-((2-allylphenoxy)methyl)-5-methylpyrazolo[1,5-a]pyrimidin-6-yl)-2-(tert-butoxy)acetate

Participants

Reaction Steps

To a stirred solution of (S)-ethyl 2-(7-(4-(allyloxy)-4-methylpiperidin-1-yl)-2-(hydroxymethyl)-5-methylpyrazolo[1,5-a]pyrimidin-6-yl)-2-(tert-butoxy)acetate (0.190 g, 0.320 mmol), 2-allylphenol (0.084 ml, 0.641 mmol) and Ph3P (0.126 g, 0.480 mmol) in THF (5 mL) was added DEAD (0.101 ml, 0.641 mmol) at 0° C. The reaction was slowly warming to rt over 3 h and after 1 h at rt, diluted with Et2O (50 mL), washed with water (2×10 mL), brine (10 mL), dried (MgSO4), filtered, concentrated and the resulting yellow residue purified by flash chromatography using 10 and 20% EtOAc/Hex to afford (S)-ethyl 2-(7-(4-(allyloxy)-4-methylpiperidin-1-yl)-2-((2-allylphenoxy)methyl)-5-methylpyrazolo[1,5-a]pyrimidin-6-yl)-2-(tert-butoxy)acetate (0.0374 g, 0.063 mmol, 19.77% yield) as colorless paste. 1H NMR (500 MHz, CDCl3) δ 7.17-7.23 (m, 2H), 7.08 (d, J=7.9 Hz, 1H), 6.94 (t, J=7.4 Hz, 1H), 6.63 (s, 1H), 6.00-6.10 (m, 2H), 5.88-5.98 (m, 1H), 5.44-5.55 (m, 1H), 5.31 (s, 2H), 5.22 (dd, J=1.3, 10.4 Hz, 1H), 4.15-4.27 (m, 2H), 4.00-4.06 (m, 2H), 3.47 (d, J=6.5 Hz, 2H), 2.62 (s, 3H), 1.88-2.06 (m, 3H), 1.68-1.77 (m, 2H), 1.37 (br. s., 3H), 1.21-1.28 (m, 12H). LCMS (M+H)=591.6.

Provenance & Evidence