Modified Glaser-Type Homocouplings: One-Pot Synthesis of Symmetrical Bisarylbutadiynes using 1,5-Diazabicyclo[4.3.0]non-5-ene (DBN), CuI and Water

Cullen, Lindsey, Joseph Furgal, Joseph Gianino, Amy Hamlin, Jessica Heidt, Bryan Vos, and Matthew Mio

The Cu (I)- and dioxygen-dependant Glaser (Cadiot-Chodkiewicz) homocoupling reaction is an excellent transformation for the generation of arylbutadiynes from terminal acetylene precursors. Our group has devised a modification to the Glaser protocol that uses trimethylsilyl-protected acetylene starting materials to generate bisarylbutadiyne oligomer products in one-pot at room temperature. Central to the modification is the utilization of the amidine base 1,5-diazabicyclo[4.3.0]non-5-ene (DBN) in the presence of CuI, water and organic solvent. The advent of innovative approaches to the generation of these oligomers should allow for rapid molecular prototyping, and in turn, increase the accessibility of valuable supramolecular and nanoscale systems.