Diethylamine → HCID 57852690, compound

Participants

Reaction Conditions

Reaction Steps

(+−)-4-Oxo-thiochroman-2-carboxylic acid (10.4 g, 50 mmol), prepared as described in T. Okubo et al (Bioorg. Med. Chem. 2004; 12: 3569-3580), in dry DCM (100 ml) was stirred under an atmosphere of nitrogen at room temperature with oxalyl chloride (12.6 g, 100 mmole) and one drop of DMF for 18 h. The reaction was then evaporated in vacuo to a gum and then redissolved in DCM (100 ml), cooled to 0° C. on an ice bath, stirred and treated dropwise with diethylamine (8.03 g, 110 mmol) in DCM (20 ml) over a period of 1 h. The reaction was allowed to warm to room temperature over 1 h and 10% aqueous potassium carbonate solution (100 ml) was added and the reaction mixture vigorously stirred. The DCM solution was separated. The aqueous solution was extracted with two further batches of DCM (100 ml) and the combined extracts were dried over magnesium sulphate. The DCM solution was concentrated in vacuo to give a dark green oil that crystallized on standing. The crystalline solid was triturated with diethyl ether (50 ml) and filtered to give the title compound (50) (8.57 g, 65%) as a pale green solid. The structure was confirmed by 1H NMR (300 MHz, CDCl3) δ 1.06 (t, J=7.1 Hz, 3H), 1.23 (t, J=7.1 Hz, 3H), 3.0-3.5 (m, 6H), 4.25 (m, 1H), 7.15-7.21 (m, 2H), 7.32-7.39 (m, 1H), 8.10-8.14 (m, 1H).

Provenance & Evidence