3-Methyl-1-pentyn-3-ol → 4-Methyl-1-{4-(methylthio)phenyl}-2-hexyn-1,4-diol

Participants

Reaction Steps

To a stirred solution of 3-methyl-1-pentyn-3-ol (23.3 g) in 150 ml anhydrous THF at −78° C. under argon, was added 130 ml of 2.5 M butyllithium in hexane dropwise over 20 minutes. The reaction solution was stirred for another 20 minutes, followed by dropwise addition 16 ml of 4-methylthiobenzaldehyde. After stirring for another 2 hours, the reaction was quenched by adding 200 ml of dilute aqueous HCl. The reaction solvent was removed in vacuo, and the resulting aqueous solution was extracted with dichloromethane (100 ml×3). The organic layer was concentrated under reduced pressure and the resulting residue was purified by column chromatography (hexane/ethylacetate=1:1) to yield 30 g of 4-methyl-1-{4-(methylthio)phenyl}-2-hexyn-1,4-diol as an oil. NMR: δ1.05 (t, J=7.5 Hz, 3H), 1.51 (s, 3H), 1.73 (m, 2H), 2.18 (s, 1H), 2.50 (s, 3H), 5.49 (s, 1,H), 7.26 (d, J=8.7 Hz, 2H), 7.45 (d, J=8.7 Hz, 2H). IR (cm−1): 3348, 2974, 2930, 1492, 1092, 983, 795, 523.

Provenance & Evidence