A method for producing a bifunctional compound of formula (1): ##STR00001##
where R.sub.1 represents COOCH.sub.3, COOC.sub.2H.sub.5, COOC.sub.3H.sub.7, COOC.sub.4H.sub.9 or CHO and R.sub.2 represents H, CH.sub.3 or C.sub.2H.sub.5, by subjecting a monoolefin of formula (2): ##STR00002##
where R.sub.1 represents COOCH.sub.3, COOC.sub.2H.sub.5, COOC.sub.3H.sub.7, COOC.sub.4H.sub.9 or CHO and R.sub.2 represents H, CH.sub.3 or C.sub.2H.sub.5, carbon monoxide and hydrogen gases to a hydroformylation reaction in the presence of a rhodium compound and an organic phosphorous compound. Compounds produced.

A method for producing a polyhydric alcohol includes: subjecting a crude reaction solution obtained by performing a reduction reaction in the presence of a hydrogenation catalyst and hydrogen using a polyhydric aldehyde having an alicyclic structure as a starting material to distillation purification. The distillation purification is performed after a content of a metal element in the crude reaction solution is 30 ppm by mass or less, and preferably 10 mass ppm or less.

A method for producing a polyhydric alcohol includes: subjecting a crude reaction solution obtained by performing a reduction reaction in the presence of a hydrogenation catalyst and hydrogen using a polyhydric aldehyde having an alicyclic structure as a starting material to distillation purification. The distillation purification is performed after a content of a metal element in the crude reaction solution is 30 ppm by mass or less, and preferably 10 mass ppm or less.

Provided are a tricyclodecane dimethanol composition, in which a ratio of isomers is controlled, and a preparation method thereof.

Provided are a tricyclodecane dimethanol composition, in which a ratio of isomers is controlled, and a preparation method thereof.

A tricyclodecane dimethanol composition comprising tricyclodecane dimethanols, wherein the tricyclodecane dimethanols comprise a chiral compound A, one of whose enantiomers represented by the following formula (I), a chiral compound B, one of whose enantiomers represented by the following formula (II), and a chiral compound C, one of whose enantiomers represented by the following formula (III), and a peak area Xc of the chiral compound C in a gas chromatogram and a total peak areas Xt of tricyclodecane dimethanols in a gas chromatogram, which are detected by a gas chromatography, satisfy Xc/Xt0.35.

The present invention is able to provide a bifunctional compound represented by formula (1).

##STR00001##

(In the formula, R.sub.1 represents COOCH.sub.3, COOC.sub.2H.sub.5, COOC.sub.3H.sub.7, COOC.sub.4H.sub.9 or CHO; and R.sub.2 represents H, CH.sub.3 or C.sub.2H.sub.5.)

The present invention is able to provide a bifunctional compound represented by formula (1).

##STR00001##

(In the formula, R.sub.1 represents COOCH.sub.3, COOC.sub.2H.sub.5, COOC.sub.3H.sub.7, COOC.sub.4H.sub.9 or CHO; and R.sub.2 represents H, CH.sub.3 or C.sub.2H.sub.5.)

A tricyclodecanedimethanol composition comprising a chiral compound A, one of enantiomers of which is represented by the following formula (I), a chiral compound B, one of enantiomers of which is represented by the following formula (II), a chiral compound C, one of enantiomers of which is represented by the following formula (III), and a chiral compound D, one of enantiomers of which is represented by the following formula (IV), wherein the number of moles of the chiral compound A, Xa and the number of moles of the chiral compound B, Xb as measured by nuclear magnetic resonance spectrometry and a total number of moles of the chiral compound A, the chiral compound B, the chiral compound C, and the chiral compound D, Xt satisfy Xa/Xt0.430 and Xb/Xt0.016:

##STR00001##

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.