Triethylamine → HCID 6455298, compound

Participants

Reaction Steps

To a solution of monic acid (1.032 g; 3 mM) and triethylamine (0.420 ml; 3 mM) in dry tetrahydrofuran (50 ml) was added diethyl phosphorochloride (0.518 g; 3 mM), at room temperature under an argon atmosphere. The mixture was stirred at room temperature for three hours and precipitated triethylamine hydrochloride was removed by filtration. The solid was washed with tetrahydrofuran and to the combined filtrate and washings was added the sodium salt of N-acetyl-β-mercaptoethylamine (0.423 g; 3 mM). The resulting suspension was stirred at room temperature for three days and then filtered through a celite plug. The solvent was removed at reduced pressure and the residue partitioned between ethyl acetate and sodium bicarbonate solution. The organic layer was washed with saturated brine and dried over anhydrous magnesium sulphate. Removal of the solvent at reduced pressure gave the crude thiol ester as a pale yellow oil. This oil was purified by column chromatography over silica gel (Type 60; 50 g). Elution with 5% methanol/chloroform afforded the pure 2-acetamidoethanethiol ester of monic acid A as a colourless oil, (0.310 g; 23%). [α]D20 -7.04° (c, 1.0 CHCl3)νmax (CHBr3) 3350, 1660 and 1625 cm-1, λmax (EtOH) 240 nm (εm 9,630), 267 nm (εm 8,390), δH (CDCl3) 6.67 (1H, broad resonance, NH); 6.02 (1H, s, CH=C); 2.17 (3H, s, CH3 --15); 1.94 (3H, s, COCH3); 1.19 (3H, d, J=6.0 Hz, CH3 --14); 0.92 (3H, d, J=6.5 Hz, CH3 --17), δc (CDCl3), 189.3, 171.0, 155.7, 124.2, 75.0, 71.1, 70.4, 68.9, 65.5, 61.1, 55.7, 42.8, 39.9, 31.7, 28.5, 23.1, 20.8, 20.3, and 12.6. m/e 327.1799 (3% C17H27O6 requires 327.1808).

Provenance & Evidence