Fragrances based on cyclic acetals

摘要

Cyclic acetal fragrances are new. Cyclic acetal fragrances (I) of formula (1) are new. R<1>,R<2>,R<3>,R<5>,R<6>,R<7>,R<9>,R<10> = H, methyl, ethyl or i-propyl; R<4> = H or together with R<3> forms a methylene (=CH2); and R<8> = 1-5C alkyl and the dotted line in the cyclic group is a single or double bond Independent claims are included for: (i) compositions containing compounds of formula (1); and (ii) a process for the production of the fragrance (I) by reaction of an aldehyde of formula (2) with a diol of formula (3) in a molar ratio of 1:0.2-1:5 in the presence of an acid catalyst and reflux agent for removal of the byproduct water at elevated temperature, cooling of the reaction mixture to 20-50 degrees C, adjustment of the pH to 6.5-7.5 by addition of dilute aqueous alkaline solution, separation of the aqueous and organic phases, washing of the organic phase with water, separation of the aqueous phase and purification by distillation.