Figure 1. Homogeneously catalysed reforming reaction of MeOH and formaldehyde.

Catalysed dehydrogenation of (a) methanol/water and (b) formaldehyde/water mixtures. The structures of representative catalysts are given by general formulas A–E and 1K (b); arrows indicate cooperative active sites in the ligand backbone. (c) Simplified sketch of the catalytic cycle highlighting the addition of water to the aldehyde and dehydrogenation of the acetal involving metal–ligand cooperation (solvent effects are neglected). A drawing of the trop unit is given at the bottom right.