Reaction Steps
To a solution of benzyl ester 85 (52.8 mg, 0.134 mmol, 1.00 equiv.) were added TEA (3.0 μL, 0.0214 mmol, 0.16 equiv.), triethylsilane (32.1 μL, 0.201 mmol, 1.50 equiv.), and Pd(OAc)2 (1.6 mg, 0.0071 mmol, 0.053 equiv.). The resulting black solution was stirred at 23° C. for 1 h then partitioned between 10 mL sat'd NH4Cl solution and 10 mL CH2Cl2. The phases were separated and the aqueous phase was extracted with 2×10 mL CH2Cl2. The combined aqueous phases were dried over MgSO4 and solvent removal by rotary evaporation left a brown oil that upon purification by silica gel column chromatography (4% HOAc in 1:1 hex:EtOAc) yielded acid 86 (34.4 mg, 85%) as a clear, colorless oil. Rf=0.17 (4% HOAc in 1:1 hex:EtOAc); 1H NMR (500 MHz, CDCl3) δ 10.09 (br s, 1H, CO2H), 7.33-7.23 (m, 5H, aryl H), 5.81 (d, 1H, J=15.9 Hz, (CH3)2CCH), 5.62 (m, 1H, CH2CH), 4.35 (s, 2H, PhCH2), 3.57 (d, 1H, J=16.6 Hz, C(O)CH2), 3.36 (d, 1H, J=16.6, Hz, C(O)CH2), 2.87 (dd, 1H, J=14.6, 7.1 Hz), 2.74 (dd, 1H, J=14.7, 7.3 Hz), 1.35 (s, 6H, (CH3)2); 13C NMR (125 MHz, CDCl3) δ 173.48, 165.44, 143.27, 139.13, 128.48, 127.66, 127.53, 120.34, 75.85, 65.24, 46.06, 37.57, 26.51, 26.29; IR (neat film) 3500-2500 (br m), 3031 (w), 2977 (m), 1843 (s), 1745 (s), 1497 (w), 1453 (w), 1149 (m) cm−1; LRMS (ESI) calc'd for C17H20O5Na 327.1; found 326.9.
