2,2-Dimethyl-3,4-epoxy-6-cyanochroman → trans-4-(2-cyanoiminothiazolidin-3-yl)-3,4-dihydro-3-hydroxy-2,2-dimethyl-2H-1-benzopyran-6-carbonitrile

Participants

Reaction Conditions

Reaction Steps

A mixture of 3,4-epoxy-3,4-dihydro-2,2-dimethyl-2H-1-benzopyran-6-carbonitrile (0.51 g), 2-cyanoiminothiazolidine (0.64 g) and pyridine (4.1 ml) was heated at 100° C. for 1.5 hours. Pyridine was removed under reduced pressure. The residue was diluted with ethyl acetate (20 ml). The solution was washed with water (20 ml and 15 ml), 5% aqueous hydrochloric acid (15 ml×2) and saturated aqueous sodium chloride (15 ml) successively, treated with charcoal, and then dried over anhydrous magnesium sulfate. The solvent was evaporated in vacuo, and the residue was triturated with ethyl acetate, to give trans-4-(2-cyanoiminothiazolidin-3-yl)-3,4-dihydro-3-hydroxy-2,2-dimethyl-2H-1-benzopyran-6-carbonitrile (0.47 g).

Provenance & Evidence