A catalyst and a process for using the catalyst are presented. The catalyst is a heterogeneous catalyst and includes active metal halides bonded to functional groups. The functional groups are bonded to a polymeric backbone to form the structure supporting the catalyst. The catalyst is useful for the dimerization of acetylene to convert the acetylene to a larger hydrocarbon, and in particular to dimerize acetylene to vinylacetylene.

A catalyst and a process for using the catalyst are presented. The catalyst is a heterogeneous catalyst and includes active metal halides bonded to functional groups. The functional groups are bonded to a polymeric backbone to form the structure supporting the catalyst. The catalyst is useful for the dimerization of acetylene to convert the acetylene to a larger hydrocarbon, and in particular to dimerize acetylene to vinylacetylene.

The object of the present invention is to provide a process for preparing a 5-alken-1-yne compound efficiently at low costs and a process for preparing (2E,6Z)-2,6-nonadienal by making use of the aforesaid process for preparing the 5-alken-1-yne compound.

There is provided a process for preparing a 5-alken-1-yne compound of the following formula (4): Y-Z-CR.sup.1CR.sup.2(CH.sub.2).sub.2CCH (4) in which Y in formula (4) represents a hydrogen atom or a hydroxyl group, the process comprising at least steps of: subjecting (i) an alkenylmagnesium halide compound prepared from a haloalkene compound of the following formula (1): Y-Z-CR.sup.1CR.sup.2(CH.sub.2).sub.2-X.sup.1 (1) and (ii) an alkyne compound of the following formula (2): X.sup.2=CCSi(R.sup.3)(R.sup.4)(R.sup.5) (2) to a coupling reaction to form a silane compound of the following formula (3): Y-Z-CR.sup.1CR.sup.2(CH.sub.2).sub.2CCSi(R.sup.3)(R.sup.4)(R.sup.5) (3); and subjecting the silane compound (3) to a desilylation reaction to form the 5-alken-1-yne compound (4).

The object of the present invention is to provide a process for preparing a 5-alken-1-yne compound efficiently at low costs and a process for preparing (2E,6Z)-2,6-nonadienal by making use of the aforesaid process for preparing the 5-alken-1-yne compound.

There is provided a process for preparing a 5-alken-1-yne compound of the following formula (4): Y-Z-CR.sup.1CR.sup.2(CH.sub.2).sub.2CCH (4) in which Y in formula (4) represents a hydrogen atom or a hydroxyl group, the process comprising at least steps of: subjecting (i) an alkenylmagnesium halide compound prepared from a haloalkene compound of the following formula (1): Y-Z-CR.sup.1CR.sup.2(CH.sub.2).sub.2-X.sup.1 (1) and (ii) an alkyne compound of the following formula (2): X.sup.2=CCSi(R.sup.3)(R.sup.4)(R.sup.5) (2) to a coupling reaction to form a silane compound of the following formula (3): Y-Z-CR.sup.1CR.sup.2(CH.sub.2).sub.2CCSi(R.sup.3)(R.sup.4)(R.sup.5) (3); and subjecting the silane compound (3) to a desilylation reaction to form the 5-alken-1-yne compound (4).

A catalyst and a process for using the catalyst are presented. The catalyst is a heterogeneous catalyst and includes active metal halides bonded to functional groups. The functional groups are bonded to a polymeric backbone to form the structure supporting the catalyst. The catalyst is useful for the dimerization of acetylene to convert the acetylene to a larger hydrocarbon, and in particular to dimerize acetylene to vinylacetylene.

The present invention relates to the use as perfuming ingredient, in particular to confer odor notes of the violet, violet leaves type, of a compound of formula (I), wherein n represents 1 or 2, A represents CH.sub.2 or CO; and R represents a C.sub.1-4 alkyl or alkenyl group or a C.sub.3 cycloalkyl group, or when A is a CH.sub.2 group R may also represent a C.sub.1-3 acyl group. Moreover, following what is mentioned herein, the present invention comprises the invention's compound as part of a perfuming composition or of a perfuming consumer product. ##STR00001##