Sodium hydride → HCID 11206816, compound

Participants

Reaction Conditions

Reaction Steps

To an oven-dried 10 mL vial was added 3-cyclohex-1-enyl-3-hydroxy-butan-2-one (0.80 g, 4.80 mmol), THF (4 mL) and trimethoxy-acetic acid methyl ester (0.94 g, 5.76 mmol). The vial was capped with a septum and flushed with Ar. In a dried round-bottom flask with stirring bar was added sodium hydride (60% dispersion in mineral oil, 0.57 g, 14.4 mmol) and THF (20 mL). The flask was capped with a septum and flushed with Ar. The contents of the vial were added dropwise via syringe to the round-bottom flask. The round-bottom flask was equipped with a condenser and septum and heated to 65° C. under Ar for 12 h. The reaction was quenched with sat'd NH4Cl (20 mL) and the layers were separated. The organic extract was concentrated and dissolved in 1,4-dioxane (4 mL). The solution was mixed with conc. HCl (0.5 mL) and stirred overnight at rt. Saturated NaHCO3 solution (20 mL) was added and the reaction was extracted with EtOAc (3×50 mL). The extracts were dried (Na2SO4), filtered and concentrated. The crude product was purified with a Biotage 25+M silica gel column using a gradient of 0-10% EtOAc in hexanes providing 0.37 g (32%) of racemic 5-cyclohex-1-enyl-5-methyl-4-oxo-4,5-dihydro-furan-2-carboxylic acid methyl ester: LC-MS) m/z 235 (M−1); 1H NMR (400 MHz, CDCl3) 6.20 (s, 1H), 5.90-5.88 (m, 1H), 3.96 (s, 3H), 2.14-2.04 (m, 3H), 1.87-1.78 (m, 1H), 1.63-1.52 (m, 4H), 1.54 (s, 3H).

Provenance & Evidence