Toluene → N-methyl-6-nitrospiro[2H-1-benzopyran-2,4'-tetrahydropyran]-4-carbothioamide

Participants

Reaction Steps

A mixture of 1.66 g of 3,4-dihydro-3-hydroxy-N-methyl-6-nitrospiro[2H-1-benzopyran-2,4'-tetrahydropyran]-4-carbothioamide, 1.0 g of p-toluenesulfonic acid monohydrate and 100 ml of toluene was refluxed with heating for 1.5 hours. Water was added therein and the mixture was extracted with methylene chloride. An organic layer was washed and dried, and the solvent was distilled. The obtained residue was purified according to silica gel column chromatography (developing solution, MeOH:CH2Cl2 =1:99) to obtain 0.93 g of N-methyl-6-nitrospiro[2H-1-benzopyran-2,4'-tetrahydropyran]-4-carbothioamide with a melting point of 223°-225° C.

Provenance & Evidence