Die oligomerisierung endständiger hydroxyacetylene mit rhodiumkomplexkatalysatoren

The substrate and ligand influence on oligomerisation of terminal hydroxyacetylenes catalysed by rhodium complexes has been studied. In this reaction α- and β-hydroxyacetylenes were compared with each other and with an unsubstituted terminal alkyne. The concentration dependant ligand control with Ph3As and Ph3P has been compared and different ligand association behaviour is found, because only with Ph3As as ligand at intermediate concentrations cyclic trimers are selectively formed. Some brief experiments with different p- and o-substituted triphenylarsines show electronic and marked steric influences on the oligomerisation of 3-methylbutyne-1-ol-3.