Rapid access to unsymmetrical 1,3-diynes and 2,5-disubstituted thiophenes under ligand and Pd/Ni-free Cu-catalysis†
Abstract
A Pd/Ni-free copper-catalysed tandem synthesis was realized for rapid access to unsymmetrical 1,3-diynes from 1,1-dibromoalkenes and terminal alkynes. This method was extended to the straightforward synthesis of unsymmetrical 2,5-disubstituted thiophenes in a one-pot operation.