A cyclic diene-containing composition having a content of a cyclic diene of 99.5 GC area % or less and a content of a cyclic monoene of 3.0 GC area % or less. A method for producing an aldehyde, the method including subjecting a cyclic diene in a cyclic diene-containing composition to a hydroformylation reaction to produce a corresponding aldehyde, wherein the method includes controlling a content of a cyclic monoene contained in the cyclic diene-containing composition to a predetermined threshold (1) or less. A method for producing a cyclic diene-containing composition, the method including performing distillation and purification of a hydrocarbon decomposition product obtained by thermal decomposition of a hydrocarbon-containing composition to produce a cyclic diene-containing composition containing a cyclic diene, wherein the method includes controlling a content of a cyclic monoene contained in the cyclic diene-containing composition to a predetermined threshold (1) or less.

A highly efficient synthesis of cis-diol compounds through cis-dihydroxylation of olefins using osmate (VI) salt as catalysts is disclosed, which has found important application in efficient large-scale preparation of, among others, ,-cedranediol from -cedrene.

A highly efficient synthesis of cis-diol compounds through cis-dihydroxylation of olefins using osmate (VI) salt as catalysts is disclosed, which has found important application in efficient large-scale preparation of, among others, ,-cedranediol from -cedrene.