Synthesis of higher spiroacetals by condensation of alkyl- and cycloalkylcyclopentanones and cyclohexanones with dihydric alcohols in the presence of heterogenic catalysts

The condensation of C 3 -C 7 alkyl- and cycloalkylcyclopentanones and cyclohexanones with 1,2-ethane-, 1,2-propane-, and 1,3-butanediols in the presence of heterogenic acid catalysts provided new representatives of spiroacetals. The highest yields of reaction products were obtained in the presence of phosphomolybdic heteropolyacid additionally modified with cobalt and bromine, and also in the presence of the chlorinated cationite KU-23 at 110–130°C. The synthesized spiroacetals possess the jasmine and menthol-wooden fragrance of various tinges.