Abstract
Hydroformylation is one of the most important homogeneously catalyzed reactions on an industrial scale. The manufacture of bulk chemicals clearly dominates. Large cobalt- and rhodium-based processes are mature technologies that have been developed over the past 80 years. Meanwhile, the potential of hydroformylation for the production of fine chemicals (perfumes, pharmaceuticals) has also been recognized. This review gives insight into the state-of-the-art of the reaction and its development. It commences with some remarks on the accidental discovery by the German chemist Otto Roelen within the historical and personal framework of the Fischer–Tropsch process, followed by the mechanistic basics of the catalytic cycle, metals used for the catalyst as well as their organic ligands. In addition, the stability of ligands and catalysts is addressed. The huge potential of this transformation is demonstrated using a variety of substrates. Finally, the use of some surrogates for syngas is discussed.
Highlights
Hydroformylation is the addition of synthesis gas (“syngas”), a mixture of CO and H2, to olefins in the presence of a catalyst to form aldehydes
Secondary phosphine oxides (SPOs) or heteroatomsubstituted secondary phosphine oxides (HASPOs) form an equilibrium consisting of a pentavalent and a trivalent species (Fig. 24)
Morimoto showed that the use of two different Rh catalysts (Rh-BINAP, Rh-Xantphos) can be beneficial, one for the decomposition of formaldehyde and the second for the hydroformylation of olefins (Fig. 44) [99]
Summary
Hydroformylation is the addition of synthesis gas (“syngas”), a mixture of CO and H2, to olefins in the presence of a catalyst to form aldehydes. The reaction leads, unless ethylene or cycloalkenes are used as a substrate, to a mixture of isomeric products, n-aldehydes (linear) and iso-aldehydes (branched). Since double bond isomerization of longer chain olefins may occur prior to the hydroformylation, different branched aldehydes can be formed even when a single terminal olefin is subjected to the reaction. In 1925, this process, where a mixture of carbon monoxide, hydrogen or water gas is converted into liquid hydrocarbons (Fig. 3) was developed by the German chemists Franz Fischer and Hans Tropsch. Saturated hydrocarbons are formed in the Fischer–Tropsch process and short and long chain
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have