Chemoselective Diels–Alder reactions of a non-symmetrical bis(carbene)-bridged ditungsten complex with 1,3-dienes

The non-symmetrical [(dimethylamino)alkenylcarbene-(methoxy)alkenylcarbene] ditungsten complex 2 undergoes Diels–Alder reactions with 2,3-dimethyl-1,3-butadiene and cyclopentadiene that proceed selectively at the methoxycarbene ligand. Similar Diels–Alder cycloadditions with the symmetrical bis[(methoxy)alkenylcarbene]ditungsten complex 1 are reported for comparison.