Sodium Carbonate → HCID 59816133, compound

Participants

Reaction Steps

Prepare a mixture of 4-Methyl-2-trifluoromethanesulfonyloxy-cyclopent-1-enecarboxylic acid methyl ester 3a (2.5 g, 8.7 mmol), 2,5-Bis-methoxymethoxy phenylboronic acid 7 (2.31 g, 9.5 mmol), tetrakis(triphenylphosphine)palladium (485 mg, 0.435 mmol), and LiCl (1.1 g, 26.1 mmol) in DME (80 mL). Add 2.0 M solution of Na2CO3 (10 mL, 21.7 mmol) and heat the reaction to reflux and stir for 2 hours. Cool the reaction to room temperature and partitioned between CH2Cl2 and saturated aqueous NaHCO3. Separate and extract the aqueous solution with CH2Cl2 (2×). Combine the organic extracts, dry (Na2SO4), filter and concentrate in vacuo. Purify by flash chromatography (125 g SiO2, 0-30% EtOAc/hexane and 30% EtOAc/hexane) to afford 2-(2,5-Bis-methoxymethoxy-phenyl)-4-methyl-cyclopent-1-enecarboxylic acid methyl ester 8a (2.4 g, 7.1 mmol, 83%) as a yellow oil. 1H NMR (δ, 400 MHz, CDCl3): 7.02 (d, 1H, J=9.2 Hz), 6.90 (dd, 1H, J=9.2, 3.1 Hz), 6.80 (d, 1H, J=3.1 Hz), 5.10 (s, 2H), 5.03 (s, 2H), 3.56 (s, 3H), 3.48 (s, 3H), 3.44 (s, 3H), 3.01-2.91 (m, 2H), 2.53-2.37 (m, 3H), 1.14 (d, 3H, J=6.6 Hz). HRMS calcd. 337.1651; found (electrospray, M+1) 337.1647.

Provenance & Evidence