cis-1,2-Cyclohexanedicarboxylic acid → Spiro[naphtho[1,2-b][1,4]oxathiine-2,4'-piperidinium]-5,6-dione cis-2-carboxycyclohexanecarboxylate

Participants

Reaction Conditions

Reaction Steps

To a mixture of spiro[naphtho[1,2-b][1,4]oxathiine-2,4′-piperidine]-5,6-dione (0.5 g, 1.66 mmol) and acetonitrile (20 ml) which had been preheated to 80° C. was added a preheated (80° C.). solution of cis-cyclohexane-1,2-dicarboxylic acid (0.286 ml, 1.66 mmol) in acetonitrile (20 ml). The reaction mixture was stirred overnight at 80° C. The resulting purple precipitate was filtered, washed with acetonitrile, and dried under reduced pressure to afford the product as a purple solid (0.472 g, 60%). M.p.=204-207° C.; 400 MHz 1H NMR (DMSO-d6) δ: 7.90-7.87 (m, 1H), 7.83-7.81 (m, 1H), 7.78-7.73 (m, 1H), 7.58-7.54 (m, 1H), 3.16-3.11 (m, 4H), 3.07-3.00 (m, 2H), 2.53-2.48 (m, 2H), 2.11-2.05 (m, 2H), 1.88-1.75 (m, 4H), 1.52-1.40 (m, 4H), 1.33-1.29 (m, 2H); LCMS: 302 [M+H].

Provenance & Evidence