A process for the preparation of a compound of formula (V):

##STR00001## comprising at least the step of reacting a compound of formula (VI)

##STR00002## with a compound (VII)

##STR00003## wherein; R.sub.2 is hydrogen or a C1-C20 hydrocarbyl radical provided that at least one R.sub.2 is not hydrogen; R.sub.5 is hydrogen or a C1-20 hydrocarbyl group optionally containing one or more heteroatoms from groups 14-16; R.sub.6 is hydrogen or a C1-20 hydrocarbyl group optionally containing one or more heteroatoms from groups 14-16; n is 1, 2 or 3; each R.sub.8 is a C1-20 hydrocarbyl group; and Hal is a halide; in the presence of a nickel imidazolidin-2-ylidene compound.

A liquid crystal composition includes one or more compounds represented by Chemical Formula 1: ##STR00001## wherein in Chemical Formula 1, A1, A2, L.sub.1 to L.sub.8, R, R, Z.sub.1 to Z.sub.3, n1, and n2 are the same as described in the specification.

A catalyst in solid particulate form free from an external carrier material comprising (I) a complex of formula (I) ##STR00001## wherein M is zirconium or hafnium; each X is a sigma ligand; L is a divalent bridge selected from R.sub.2C, R.sub.2CCR.sub.2, R.sub.2Si, R.sub.2SiSiR.sub.2, R.sub.2Ge, wherein each R is independently a hydrogen atom, C1-C20-alkyl, tri(C1-C20-alkyl)silyl, C6-C20-aryl, C7-C20-arylalkyl or C7-C20-alkylaryl; each R.sub.2 is independently hydrogen or a C1-C20 hydrocarbyl radical provided that at least one R.sub.2 is not hydrogen; each R.sub.5 is independently hydrogen or a C1-20 hydrocarbyl group optionally containing one or more heteroatoms from groups 14-16; each R.sub.6 is independently hydrogen or a C1-20 hydrocarbyl group optionally containing one or more heteroatoms from groups 14-16; each n is independently 1, 2 or 3; and each R.sub.8 is a C1-20 hydrocarbyl group; and (ii) a cocatalyst comprising a compound of a group 13 metal, e.g. Al or boron.

A catalyst in solid particulate form free from an external carrier material comprising (I) a complex of formula (I) ##STR00001## wherein M is zirconium or hafnium; each X is a sigma ligand; L is a divalent bridge selected from R.sub.2C, R.sub.2CCR.sub.2, R.sub.2Si, R.sub.2SiSiR.sub.2, R.sub.2Ge, wherein each R is independently a hydrogen atom, C1-C20-alkyl, tri(C1-C20-alkyl)silyl, C6-C20-aryl, C7-C20-arylalkyl or C7-C20-alkylaryl; each R.sub.2 is independently hydrogen or a C1-C20 hydrocarbyl radical provided that at least one R.sub.2 is not hydrogen; each R.sub.5 is independently hydrogen or a C1-20 hydrocarbyl group optionally containing one or more heteroatoms from groups 14-16; each R.sub.6 is independently hydrogen or a C1-20 hydrocarbyl group optionally containing one or more heteroatoms from groups 14-16; each n is independently 1, 2 or 3; and each R.sub.8 is a C1-20 hydrocarbyl group; and (ii) a cocatalyst comprising a compound of a group 13 metal, e.g. Al or boron.

A liquid crystal composition includes one or more compounds represented by Chemical Formula 1:

##STR00001## wherein in Chemical Formula 1, A1, A2, L.sub.1 to L.sub.8, R, R, Z.sub.1 to Z.sub.3, n1, and n2 are the same as described in the specification.

The present invention relates to 2-(2,4,5-trimethylcyclohex-2-en-1-yl)acetaldehyde and derivatives thereof, to a process for preparing said compounds, to the use of 2-(2,4,5-trimethylcyclohex-2-en-1-yl)acetaldehyde or a specific derivative thereof or of mixtures of said compounds or of a stereoisomer thereof or of a mixture of two or more stereoisomers thereof as aroma chemicals; to the use of 2-(2,4,5-trimethylcyclohex-2-en-1-yl)acetaldehyde or a specific derivative thereof for modifying the scent character of a fragranced composition; to compositions containing 2-(2,4,5-trimethylcyclohex-2-en-1-yl)acetaldehyde or a specific derivative thereof or a mixture of said compounds or a stereoisomer thereof or a mixture of two or more stereoisomers thereof; and to a method of preparing a fragranced composition or for modifying the scent character of a fragranced composition, comprising incorporating 2-(2,4,5-trimethylcyclohex-2-en-1-yl)-acetaldehyde or a specific derivative thereof or a mixture of said compounds or a stereoisomer thereof or a mixture of two or more stereoisomers thereof into said composition.

The present invention relates to 2-(2,4,5-trimethylcyclohex-2-en-1-yl)acetaldehyde and derivatives thereof, to a process for preparing said compounds, to the use of 2-(2,4,5-trimethylcyclohex-2-en-1-yl)acetaldehyde or a specific derivative thereof or of mixtures of said compounds or of a stereoisomer thereof or of a mixture of two or more stereoisomers thereof as aroma chemicals; to the use of 2-(2,4,5-trimethylcyclohex-2-en-1-yl)acetaldehyde or a specific derivative thereof for modifying the scent character of a fragranced composition; to compositions containing 2-(2,4,5-trimethylcyclohex-2-en-1-yl)acetaldehyde or a specific derivative thereof or a mixture of said compounds or a stereoisomer thereof or a mixture of two or more stereoisomers thereof; and to a method of preparing a fragranced composition or for modifying the scent character of a fragranced composition, comprising incorporating 2-(2,4,5-trimethylcyclohex-2-en-1-yl)-acetaldehyde or a specific derivative thereof or a mixture of said compounds or a stereoisomer thereof or a mixture of two or more stereoisomers thereof into said composition.

A method of reducing an aromatic ring or a cyclic, allylic ether in a compound includes preparing a reaction mixture including a compound including an aromatic moiety or a cyclic, allylic ether moiety, an alkali metal, and either ethylenediamine, diethylenetriamine, triethylenetetramine, or a combination thereof, in an ether solvent; and reacting the reaction mixture at from 20 C. to 30 C. for a time sufficient to reduce a double bond in the aromatic moiety to a single bond or to reduce the cyclic, allylic ether moiety.

A method of reducing an aromatic ring or a cyclic, allylic ether in a compound includes preparing a reaction mixture including a compound including an aromatic moiety or a cyclic, allylic ether moiety, an alkali metal, and either ethylenediamine, diethylenetriamine, triethylenetetramine, or a combination thereof, in an ether solvent; and reacting the reaction mixture at from 20 C. to 30 C. for a time sufficient to reduce a double bond in the aromatic moiety to a single bond or to reduce the cyclic, allylic ether moiety.

The present application relates to bicyclo[2.2.1]hept-5-en-2-ol and related compounds, methods of making them, and methods of using them as flavor and fragrance ingredients in food, cosmetic, pharmaceutical, consumer, and other compositions and products.