Octanoic Acid → HCID 16661879, compound

Participants

Reaction Steps

To a 100 ml round bottom flask equipped with a stir-bar was added 3,5-diisopropyl-2-methyl-[1,4]benzoquinone (216, see Example 2D; 1.03 g, 5.00 mmol), octanoic acid (83211, 757 mg, 5.24 mmole), silver (I) nitrate (917 mg, 5.40 mmol), acetonitrile (35 ml), and water (25 ml). The solution was heated under balloon-closed ambient atmosphere to 75° C. and was homogenous. Potassium persulfate (1.28 g, 5.75 mmol) in water (30 ml) was then added dropwise over 4 hours via syringe pump. Following complete addition the reaction mixture was heated for a further 2 hours and then the reaction volume reduced by approximately half under reduce pressure on a rotary evaporator. Water (50 ml) was added to the concentrate and the mixture extracted with MTBE (3×50 ml). The combined organics were washed with brine (50 ml), dried (sodium sulfate), and concentrated to a yellow oil (1.2 g). Approx. 75% of the residue was purified in 150-200 mg portions by preparative-TLC [silica gel: 200×200×2 mm; 100% heptane loading; 5% ethyl acetate/heptane elution]. The fastest running bands, as visualized by UV, were combined, extracted from the silica gel with MTBE, and the extract concentrated to a yellow oil (˜300 mg). The residue was further purified by flash chromatography [silica gel: 120 g; 100% heptane loading; 3-6% ethyl acetate/heptane gradient elution] to give the 2-heptyl-3,5-diisopropyl-6-methyl-[1,4]benzoquinone (218) as a bright yellow oil (288 mg, 21% mass yield). 1H NMR (400 MHz; C6D6; ppm): 2.93-2.80 (m, 2H), 2.49-2.46 (m, 2H), 1.84 (s, 3H), 1.43-1.18 (m, 10H), 1.33 (d, J=6.8 Hz, 6H), 1.19 (d, J=6.8 Hz, 6H), 0.88 (t, J=7.2 Hz, 3H).

Provenance & Evidence