HCID 15312642, compound → HCID 19793897, compound

Participants

Reaction Conditions

Reaction Steps

The known 5-oxo-7-(trimethylsilyl)hept-6-ynoic acid (1.15 g, 2; prepared using the procedure described in J. Org. Chem., Vol. 62, No. 4, 1997, p. 982-991) was dissolved in methanol (40 ml) and a solution of Borax (Na2B4O7×10H2O, 2.7 g) in water (6 ml) was added. The resulting reaction mixture was stirred for 18 h at 45° C. under argon. The reaction mixture was then quenched by the addition of 1 M HCl (20 ml) and methanol removed in vacuo. The remaining aqueous solution was then extracted with ethyl acetate (4×35 ml). After washing the pooled organic extracts with brine (2×40 ml), drying with MgSO4 and then filtering, volatiles were removed in vacuo. The crude orange oil remaining was purified by flash chromatography (5% ethyl acetate→10%→15% ethyl acetate/hexane) yielding a pale yellow oil product, 5-oxohept-6-ynoic acid (328 mg, 3), which crystallized under storage. 1H NMR (400 MHz, CDCl3): δ1.75 (m, 2H), 2.22 (t, 2H), 2.63 (t, 2H), 4.8 (s, 1H).

Provenance & Evidence