Sulfuric Acid → (3AS,6aR)-1,3-dibenzyltetrahydro-1H-furo(3,4-d)imidazole-2,4-dione

Participants

Reaction Steps

A mixture of the amide-alcohol (3.0 g) prepared in Example 8, dioxane (30 ml) and 20 % sulfuric acid (20 ml) is refluxed with stirring for 1 hour. After the reaction is completed, the mixture is concentrated to one third of the original volume and diluted with water (50 ml). The precipitate is filtered to give cis-1,3-dibenzyl-hexahydrofuro[3,4-d]imidazole-2,4-dione (1.53 g, 84.5 %). M.P. 106.5° to 109° C. [α]D20 + 2.6° (C = 2 in CHCl3). The infrared spectrum of the sample is identified with that of the authentic sample.

Provenance & Evidence