Ethanol → HCID 18988249, compound

Participants

Reaction Steps

Part C. A solution of the ester compound from Part B above (4.53 g, 14.5 mmol) and sodium hydroxide (0.25N solution) in 95% ethanol (120 mL, 30.0 mmol NaOH) was stirred for 12 hours at ambient temperature. The reaction mixture was evaporated, and the residue acidified with hydrochloric acid (1N, 150 mL). This was saturated with sodium chloride and extracted with methylene chloride (2×200 mL). The extracts were combined, dried over anhydrous magnesium sulfate, filtered and evaporated to afford the product, 3,6-dipentyl-3,6-dihydro-2H-thiopyran-2-carboxylic acid, as an oily mixture of diastereomeric products (5:1 by NMR) (4.01 g, 14.1 mmol, 97%). 1H NMR (major isomer; CDCl3): δ 5.73 (2H, s); 3.48 (1H, br t, J=7 Hz); 3.40 (1H, d, J=3.7 Hz); 2.60-2.52 (1H, m); 1.71-1.24 (16H, m); 0.89 (6H, t, J=3.7 Hz). Mass spectrum (NH3 -CI/DDIP): m/z 287 (6%); 286 (18%); 285 (100%); 239 (25%); 211 (2%).

Provenance & Evidence