combination of cationic rhodium(I) complexes with N-phosphino tert-butylsulfinamides (PNSO) ligands is efficient for catalytic intra- and intermolecular [2+2+2] cycloaddition reactions. PNSO ligands are a new class of chiral bidentate ligands, which have the characteristic of combining the easily accessible sulfur chirality with the coordinating capacity of phosphorous. Cycloaddition of open-chained and
Disclosed is a process for production of a substituted benzene, which comprises intramolecularly and/or intermolecularly trimerizing a triple bond in an alkyne in the presence of a transition metal catalyst to yield a substituted benzene compound. In the process, the transition metal catalyst is prepared from an iminomethylpyridine represented by the formula (1) or (2), a transition metal salt or a hydrate thereof, and a reducing agent in a reaction system and is used to perform the trimerization. The process can be used in any one of the intramolecular cyclization of a triyne compound, the cyclization of a diyne compound or an alkyne compound and the intermolecular cyclization of three molecules of an alkyne compound, is excellent in economic effectiveness and operability, and is practically advantageous.
wherein R
1
and R
3
independently represent a linear or cyclic C
1
-C
20
aliphatic hydrocarbon group or the like; R
2
represents a hydrogen atom or the like; X represents a hydrogen atom, O or the like; and Y represents O, S or the like.