Dimethylformamide → HCID 86209319, compound

Participants

Reaction Steps

A solution of 1,1-dioxo-hexahydro-1λ6-thiopyran-4-carboxylic acid (10.2 g, 57.3 mmol) [prepared according to the procedure of Org. Prep. Proc. Int. 1977, 94] and DMF (0.3 ml) in DCM (120 ml) at rt, was treated dropwise with oxalyl chloride and the resulting slurry stirred for 3 d. The crude reaction was then concentrated in vacuo to give an oil which was re-dissolved in THF (100 ml), treated with ethoxyacetylene (10 ml, 50% w/w) and triethylamine (10 ml) and the resulting slurry stirred for 10 d at rt. Filtration and concentration of the filtrate in vacuo gave a crude oil which was purified by chromatography (SiO2, 30% EtOAc:hexanes) to give the title compound as a yellow oil (8.9 g, 38.6 mmol, 67%). δH (CDCl3, 300K) 4.88 (1H, s), 4.27 (2H, q, J 7.1 Hz), 3.44–3.37 (2H, m), 3.13–3.05 (2H, m), 2.47–2.40 (2H, m), 2.35–2.29 (2H, m), 1.48 (3H, t, J 7.1 Hz); m/z (ES+, 70V) 230.9 (MH+).

Provenance & Evidence