A novel agent for introducing a protecting group for a hydroxy group and/or a mercapto group that can be introduced and removed under mild conditions is provided. The agent for introducing a protecting group for a hydroxy group and/or mercapto group of a substrate compound having the hydroxy group and/or mercapto group is represented by the following formula (I), wherein A represents a ring structure having 1 to 5 rings in which two carbon atoms of an adjacent benzene ring are included, the ring structure comprises a substituted or unsubstituted five-membered ring or six-membered ring and optionally include a heterocycle; each of R.sup.1, R.sup.2, R.sup.3, and R.sup.4 is independently a hydrogen atom or a linear or branched alkyl group having 1 to 5 carbon atoms; and X is a halogen atom or OSO.sub.2R.sup.5 (R.sup.5=an aryl group or an alkyl group).

A novel agent for introducing a protecting group for a hydroxy group and/or a mercapto group that can be introduced and removed under mild conditions is provided. The agent for introducing a protecting group for a hydroxy group and/or mercapto group of a substrate compound having the hydroxy group and/or mercapto group is represented by the following formula (I), wherein A represents a ring structure having 1 to 5 rings in which two carbon atoms of an adjacent benzene ring are included, the ring structure comprises a substituted or unsubstituted five-membered ring or six-membered ring and optionally include a heterocycle; each of R.sup.1, R.sup.2, R.sup.3, and R.sup.4 is independently a hydrogen atom or a linear or branched alkyl group having 1 to 5 carbon atoms; and X is a halogen atom or OSO.sub.2R.sup.5 (R.sup.5=an aryl group or an alkyl group).

The present invention relates to a novel process for the preparation of 9-dichloromethylene-1,2,3,4-tetrahydro-1,4-methano-naphthalen-5-ylamine which process comprises a) reacting cyclopentadiene in the presence of a radical initiator and CXCl.sub.3, wherein X is chloro or bromo, to a compound of formula II ##STR00001## aa) reacting cyclopentadiene with CXCl.sub.3, wherein X is chloro, in the presence of a metal catalyst to a compound of formula II ##STR00002## wherein X is chloro, b) reacting the compound of formula II with a base in the presence of an appropriate solvent to the compound of formula III ##STR00003## c) and converting the compound of formula III in the presence of 1,2-dehydro-6-nitrobenzene to the compound of formula IV ##STR00004## and d) hydrogenating the compound of formula IV in the presence of a metal catalyst.

A polymer compound is provided having a constitutional unit represented by the following formula (1): ##STR00001##
wherein: R.sup.1 and R.sup.2 represent an alkyl group, an aryl group, a mono-valent aromatic heterocyclic group, an alkoxy group or an aryloxy group, and Ar.sup.1 represents an arylene group or a di-valent condensed polycyclic aromatic heterocyclic group.

A polymer compound is provided having a constitutional unit represented by the following formula (1): ##STR00001##
wherein: R.sup.1 and R.sup.2 represent an alkyl group, an aryl group, a mono-valent aromatic heterocyclic group, an alkoxy group or an aryloxy group, and Ar.sup.1 represents an arylene group or a di-valent condensed polycyclic aromatic heterocyclic group.

Clean process for preparing a chloroformyl-substituted benzene by oxidation of a tail gas hydrogen chloride from a chlorination reaction and a chloroacylation reaction and recycling of the resulting oxidation product chlorine gas into the chlorination reaction. The present invention provides a clean process for preparing a polymer-grade chloroformyl-substituted benzene.

Clean process for preparing a chloroformyl-substituted benzene by oxidation of a tail gas hydrogen chloride from a chlorination reaction and a chloroacylation reaction and recycling of the resulting oxidation product chlorine gas into the chlorination reaction. The present invention provides a clean process for preparing a polymer-grade chloroformyl-substituted benzene.

A solid-supported catalyst ligand which chelates palladium (II) species to form a complex that functions as a heterogeneous catalyst that is stable and can be recycled without significantly losing any catalytic activity in a variety of chemical transformations, a method for producing the solid-supported catalyst ligand and a method for catalyzing a palladium cross-coupling reaction, such as the Suzuki-Miyaura, Mizoroki-Heck, and Sonagashira reactions.

A solid-supported catalyst ligand which chelates palladium (II) species to form a complex that functions as a heterogeneous catalyst that is stable and can be recycled without significantly losing any catalytic activity in a variety of chemical transformations, a method for producing the solid-supported catalyst ligand and a method for catalyzing a palladium cross-coupling reaction, such as the Suzuki-Miyaura, Mizoroki-Heck, and Sonagashira reactions.

The invention provides a liquid crystal compound satisfying at least one of physical properties such as a high stability to heat or light, a high clearing point (or a high maximum temperature), a low minimum temperature of a liquid crystal phase, a small viscosity, a suitable optical anisotropy, a small dielectric anisotropy, a suitable elastic constant and a good compatibility with other liquid crystal compounds, a liquid crystal composition including this compound, and a liquid crystal display device containing this composition. The invention provdes a compound represented by formula (1):

##STR00001##

where R.sup.1 and R.sup.2 is alkyl having 1 to 20 carbons or the like; one of L.sup.1 and L.sup.2 is both hydrogens, and the other is both fluorines; Z.sup.1 and Z.sup.2 are independently a single bond, —COO—, —OCO—, —OCH.sub.2—, —CH.sub.2O—, —CF.sub.2O—, —OCF.sub.2—, —CH.sub.2CH.sub.2—, —CH═CH—, —C≡C— or the like.