Isomerization–Hydroformylation Tandem Reactions

Abstract

The metal-catalyzed isomerization−hydroformylation tandem reaction is of great importance for the production of linear aldehydes starting from internal olefins, but also, the shift of the double bond from a terminal position into the interior of an alkyl chain and the subsequent hydroformylation can be of interest. This review aims to summarize problems and achievements in this area under particular consideration of results published by the Leibniz-Institut fur Katalyse (LIKAT) in the past two decades. A main focus is given to the variation of metals (Co, Rh, Ru, Pd, Pt, Fe) and phosphorus ligands used for the tandem reaction.

Rhodium-Biphephos-Catalyzed Tandem Isomerization–Hydroformylation of Oleonitrile

“…Several challenges are met in this tandem process: (i) internal alkenes are thermodynamically more stable than terminal ones, which are therefore (dynamically) formed in minutes amounts [5,6]; (ii) hydroformylation and isomerization are competitive reactions, and hence various (undesired) branched aldehydes can be obtained; and (iii) rather facile competitive hydrogenation of all kinds of C=C bonds often plagues the chemoselectivity of the reaction. Rhodium-catalyzed tandem isomerization-hydroformylation of middle-chain alkenes (<10 C) has been widely studied over the last two decades, generally with bulky ligands [7,8]. Regioselectivities in the range l/b = 95:5-98:2 were obtained with 2-alkenes (e.g., 2-hexene, 2-octene) [9][10][11][12][13][14], while with 4-octene regioselectivities up to l/b = 89:11 were observed [15,16].…”

Influence of electrostatic repulsive force and electron-withdrawing effect in ionic diphosphine on regioselectivity of rhodium-catalyzed hydroformylation of 1-octene

“…Reasonably, the higher pressure of syngas led to more rapid hydroformylation, indicating that the pressure of syngas kinetically It has been widely known that even the small change in the structures of the coordinated phosphines corresponding to the electronic and steric effects will dramatically influence the Rh-complex catalyzed hydroformylation [22]. Herein, the structure information on ligand 1 and 2 as given in Fig.…”

Rhodium/Phosphine catalysed selective hydroformylation of biorenewable olefins

“…It is also called as oxo process for the conversion of olefins into aldehydes, alcohols, carboxylic acid and derivatives in presence of transition metal catalyst under syngas (CO/H 2 ) pressure . It is atom economical process, however it has challenges in controlling the selectivity of products, isomerisation and hydrogenation . Although the conversion of terminal olefins proceeded well, the hydroformylation of internal olefins is difficult to provide aldehydes with high regioselectivity .…”