Ammonium Chloride → (2z)-4-{[Tert-butyl(dimethyl)silyl]oxy}-2-[4-(methylsulfonyl)phenyl]-3-phenylbut-2-enyl n-(tert-butoxycarbonyl)glycinate

Participants

Reaction Steps

To a solution of 16.4 g of (2Z)-4-{[tert-butyl(dimethyl)silyl]oxy}-2-[4-(methyl-sulfonyl)phenyl]-3-phenylbut-2-en-1-ol, 1.92 g of DMAP and 7.30 g of Boc-Glycine in 125 mL of CH2Cl2 at 0° C. was added 8.0 g of EDCl. The reaction mixture was stirred for 4 h. Then saturated ammonium chloride solution was added and extracted with EtOAc. The organic layer was combined, washed with brine and dried over Na2SO4. The solvent was evaporated and the residue was purified by flash chromatography over silica gel (5–55% EtOAc/hexane) to afford 22 g of the titled compound as a colorless oil. 1H (500 MHz, acetone-d6): δ 7.67 (d, 2H), 7.34 (d, 2H), 7.13–7.04 (m, 5H), 6.26 (br s, NH), 5.23 (s, 2H), 4.76 (s, 2H), 3.73 (d, 2H), 3.02 (s, 3H), 1.40 (s, 9H), 0.81 (s, 9H), −0.01 (s, 6H).

Provenance & Evidence