Depict the molecular orbital diagrams for the pi molecular orbitals of ethylene and 1,3 butadiene. State the HOMO and LUMO for each molecule.
1. Show 2 possible ways to combine the molecular orbitals of 1,3 butadiene and ethylene to get constructive overlap.
-Utilizing molecular orbital diagrams, explain why ethylene plus ethylene cycloadditions don't take place thermally but are allowed photochemically.
-Forecast whether a [4+4] cycloaddition reaction between 2 molecules of butadiene will take place thermally or photochemically.