The oligomerisation of phenylacetylenes with rhodium(I) and P ligands as the catalytic system

Abstract The dependence of the oligomerisation of phenylacetylene to cyclotrimers and dimers upon a Rh(I) complex with different P ligands as the catalytic system has been studied. The influence of substituents in the phenyl ring of the substrate has been examined as well. A selective cyclotrimerisation of phenylacetylenes is achieved with [1,5-C6H10RhCl]2 as the catalyst. A decrease of the selectivity appears with very bulky o-substituents or a substitution in the 2,6-position of phenylacetylene. [P]-control maps indicate a mono-association of the ligand accompanied by a reduced activity of the system. The second association of a P ligand results in an inhibition of the cyclotrimerisation …