Hydroformylation of 1-dodecene

Since it is well known that the higher the olefin, the more difficult it is to hydroformylate, we tried our approach on 1-dodecene. We found that when we used 50 50 ethanol/water (R24) and CTAB only (R33) systems they showed no activity for hydroformylation of 1-dodecene whereas, the addition of surfactant to the 50 50 ethanol/water mixture (R27) dramatically increased the reaction rate, as well as the selectivity. 

A series of water-soluble polyether-substituted triphenyl phosphines (PETPPs) la-c has been successfully employed by Jin et al. [11] in the thermoregulated hydroformylation of 1-dodecene in the biphasic water/toluene system. The catalysts exhibit very good catalytic properties with conversions up to 93% and about 85% selectivity for aldehyde formation. The catalyst derived from rhodium(III) chloride and ligand Ic could be reused in four consecutive cycles without significant loss of activity or chemoselectivity. The n-selectivity of the product aldehydes was not determined. 

Rh/76 (Table 4 n=l, x=0, R= Me, Bu), which should be able to induce micelle formation, were used as catalysts in the biphasic hydroformylation of 1-dodecene.371 The conversion was 80%, the n/i ratio 60/40 with no carry-over of the rhodium catalyst into the organic phase.371... 

Rh/tppts catalysed hydroformylation of 1-dodecene was carried out in highly stable microemulsions generated by conventional surfactants e.g. sodium dodecyl sulfate and co-surfactants (butanol) which breaks after the reaction into two phases facilitating catalyst recovery 4,4... 

Recently, the hydroformylation of 1-dodecene and cyclohexene by the dinuclear doubly bridged pyrazolate complexes [(PR3)(CO)Rh(/i-pz )]2, 46-49, was reported (75). Thus, at 120°C and at a CO and H2 pressure of 28 atm, these two olefins were transformed into the corresponding aldehydes with greater than 95% yield. All four complexes catalyze the transformation of 1-dodecene to 1-undecane-carboxaldheyde in preference to the iso compound, although this regioselectivity is rather poor (75). 

Haumann, M., Koch, H., Hugo, R and Schomacker, R. (2002) Hydroformylation of 1-dodecene using Rh-TPPTS in a microemulsion. Appl. Catal. A, 225, 239-249. 

Rhodium complexes generated from the polyethylene glycol)-functionalized phosphine 9 (n = 1, x = 0, R = Me, Bu), which should behave as a nonionic surfactant and be able to induce micelle formation, have been used as catalysts in the hydroformylation of 1-dodecene in an aqueous/organic two-phase system [31]. The conversion of 1-dodecene was 80% and the n/iso ratio 60 40, with no carryover of the rhodium catalyst into the organic phase. The Rh/9 (n = 1, x = 0, R = Me, Bu) catalyst remained active after one recycle step [31],... 

Hydroformylation of 1-dodecene to tridecaldehydes RhCl(CO) (TPPTS )2 G-L-L/water soluble catalysis [9]... 

Table 4 indicated the recycling efficiency of PETPP/Rh complex in the hydroformylation of 1-dodecene. By convenient decantation, the catalyst could be easily isolated from organic phase and directly reused in the next reaction runs. After eight recycles, almost no loss in reactivity has been observed. 

In another report a semi-empirical rate equation has been proposed combining mechanisms of homogeneous and interfacial parameters for biphasic hydroformylation of 1-dodecene with water-soluble Rh-complex catalyst [36]. 

Interfacial kinetics of biphasic hydroformylation of 1-dodecene catalyzed by water-soluble rhodium complex have been studied by a combined numerical and experimental approach [54]. 

Figure 1 Variation of Xj and nji of hydroformylation of 1 -dodecene versus stirrer speed (N) [11.

Several chemical engineering factors affect the biphasic hydroformylation of 1-dodecene in a gas-hquid-Hquid three-phase reachon system. In previous research [1], effects of temperature, total pressure, H2/CO molar raho, catalyst and ligand concentration, olefin concentration, surfactant concentration, and organic/ aqueous-phase volume ratio on the hydroformylation kinetics were studied with... 

Table 4 Effect of agitation configuration on hydroformylation of 1-dodecene [5].

Figures Hydroformylation of 1-dodecene catalyzed by Rh/[PrMIM][Ph2P 3-C5H4S03)] in a variety of ILs. The percentages are conversions of 1-dodecene in the isolated fractions. (Reprinted with permission from [16], 2003 American Chemical Society).

Microemulsions containing the aqueous Rh-catalyst solution dispersed in a large oily phase of the substrate olefin and product aldehydes can also be formed using relatively large amount of surfactants (155). The application of this technique was demonstrated in hydroformylation of 1-dodecene using either an anionic or a nonionic surfactant (Na-dodecylsulfate and Marlipal 01370, respectively) the catalyst was prepared in situ from Rh(I)-precursors and TPPTS. At... 

As a result of complete isomerization in the hydroformylation of 1-dodecene at 150-200° C, the formation of all possible dodecene isomers has been detected (76). 

For example, hydroformylation of 1-dodecene has been carried out with a phosphabicyclononane-modified Co catalyst at 8.5 MPa syngas pressure (CO/H2 = 1 2) at 120 °C with a Co/P ratio of 1 2 to produce 55% isomeric Cj g alcohols [61]. RhClj immobilized on trioctylmethylammonium chloride operating in a multiphase Uquid system together with isooctane and water was developed for the conversion of tetradecene [62]. In more sophisticated approaches, phosphorus-modified Rh catalysts have been screened in biphasic systems, sometimes containing surface-active compounds [63]. Even internal olefins, such as (Z)-2-tridecene, have been used as substrates. Thus, by using a mixed, homogeneous Rh/Ru catalyst in a hydroformylation-hydrogenation protocol, 1-tetradecanol was obtained with a yield of 83% and with an Hb selectivity of 12 (see Section 5.2) [64]. 

A typical benchmark system is the Shell catalyst for reductive hydroformylation of 1-dodecene based on the mixture of Phobane-C2o ligands, which operates under a syngas pressure of 85 bar with an excess of H2 in comparison to CO to give 86.9% yield of isomeric tridecanols (Scheme 5.44) [46a]. 1-Tridecanol is used as a lubricant or as an ingredient of surfactants, ink solvents, and pesticides. 

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