Hydroformylation 1-dodecene

HP IR measurements have recently been reported by workers at Sasol for cobalt-catalysed 1-dodecene hydroformylation reactions using bicyclic phosphines (4) derived from (R)-(+)-limonene [68]. Using Fourier deconvolution to separate absorptions due to [HCo(CO)4] and [Co2(CO)7(phosphine)], it was possible to estimate the ratio of modified [HCo(CO)3(phosphine)] to un-modified [HCo(CO)4] in the catalytic mixture, using peak areas. Values of this ratio ranged from ca. 2-20, depend-... 

Figure 4 Influence of agitation speed on the conversion and regioselectivity of 1-dodecene hydroformylation [5],...

As shown in Table 4 and Figure 5, the single PBTU impeller (Case 2) achieved a better performance with a higher initial rate and n/i aldehyde ratio accompanied by a lower power consumption than the single DT impeller (Case 1) under the same conditions of operation. This was possibly due to the better capability for overall circulation and lower agitation intensity of the PBTU impeller, which favored maintenance of the orderly micelle structure. When the novel SRFB was used (Cases 3 and 5), the initial rate of the biphasic hydroformylation increased remarkably from 0.630 10 kmol m (Case 1) to 1.24 10 and 2.03 10 kmol m respectively, by a factor of almost 2-3. However, the conversion and regioselectivity after 2 h of reaction were almost the same. Therefore, it is clear that an SRFB can increase the initial rate of 1-dodecene hydroformylation, but fails to further enhance... 

The catalysts obtained were highly active in the hydroformylation of higher alkenes and styrene at 80-120 °C, whereas their activity below the cloud point proved to be low (Table 11-1). Note also that the activity of the catalysts substantially exceeded the activity exhibited under similar conditions by a catalytic system involving rhodium complexes with sulfonated phosphines and oligo(ethylene oxide). Using phosphine 20, a turnover frequency (TOP) in dodecene hydroformylation of 1280 h was obtained All the catalysts could be reused. 

Scheme 5.1 Dicationic surfactants used in aqueous 1-dodecene hydroformylation [4].

Figure 5.1 Influence of spacer in dicationics and of a second long alkyl chain in a classical monocationic on TOF of aqueous 1-dodecene hydroformylation [4] (A) CTAB, ( ) G(Xyl),...

Propjiene (qv) [115-07-1] is the predominant 0x0 process olefin feedstock. Ethylene (qv) [74-85-1J, as well as a wide variety of terminal, internal, and mixed olefin streams, are also hydroformylated commercially. Branched-chain olefins include octenes, nonenes, and dodecenes from fractionation of oligomers of C —C olefins as well as octenes from dimerization and codimerization of isobutylene and 1- and 2-butenes (see Butylenes). 

Thermomorphic solvent mixtures have been tested for hydroformylation of 1-octene and 1-dodecene to determine the ease of product recovery and catalyst recycling. Using both batch and continuous reactors, we demonstrated the efficacy of a biphasic, thermomorphic, system that had the following advantages ... 

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. 

In summary, what we have found is that the combination of a thermomorphic system and a surfactant is very effective for the hydroformylation of 1-octene and 1-dodecene. We believe that although a 90 10 ethanol/water and heptane system becomes miscible at 70°C, the additional water in a 50 50 ethanol/water and heptane system raises the miscibility temperature to >100°C. When a surfactant is added, the miscibility temperature is lowered and the biphasic solution becomes monophasic below the reaction temperature, resulting in good reaction rates. In addition, the presence of the surfactant also enhances the selectivity compared to the completely homogeneous system from 1.8 to 5.3 L/B... 

We have developed a thermomorphic catalyst system for the hydroformylation of higher alkenes. We have built a bench-scale continuous reactor and have used it to determine the long-term performance of the thermomorphic catalyst system. Longterm results (>400 h) using 1-octene and 1-dodecene show that the catalyst has high selectivity and no measurable loss in activity. 

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. 

Hydroformylations were also carried out in IL/SCCO2 biphasic reaction systems [7]. In particular, it was demonstrated that continuous-flow systems could be operated successfully for the Rh-catalysed hydroformylation of hex-I-ene [24] and I-dodecene [25]. 

Concerning monodentate amphiphilic phosphines one of the latest developments is the use of Rh/phosphonate-phosphine catalysts for the hydroformylation of 1-octene and 1-dodecene [54]. The catalysts were prepared in situ from [Rh(acac)(CO)2] and from the appropriate Ph2P(CH2)ioP03M2 (M = Na, K", NKi, l aPr) phosphine. Pretreatment under 30 bar syngas significantly improved the catalytic performance. At 120 °C, 30 bar syngas, [P]/[Rh] = 5, in 4 h, 1-octene reacted with 52 % conversion and 47 % aldehyde yield. This means a 91 % selectivity to... 

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... 

Figure 7.4. Molar paraffin-to-aldehyde yield ratios in hydroformylation of n-dodecene catalyzed by HCo(CO)3Ph at 185°C as function of H2-to-CO ratio at different total pressures [11].

Based on their chain length, olefins converted in commercial oxo plants are divided into four groups ethylene (C2), propene (C3), butene to dodecene (C4 to Cl2) and longer-chain olefins (> C12). The factors influencing product distribution and reaction rates in the hydroformylation of olefins will be discussed in Section 2.1.1.3.3. The economical aspects of 0x0 processes are described in Section 2.1.1.4.1. The share of various products in the overall olefin hydroformylation capacity is C2 2%), C3 (73%), C4-C12 (19%) and >Ci2 (6%). 

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). 

Using RuCl(CO)(TPPTS)(BISBIS) the biphasic aqueous hydroformylation of higher olefins in the presence of the cationic surfactant CTAB ensures a TOF > 700 h and regioselectivity >96% for the linear aldehyde Piperazinium cationic surfactants were also successfully applied as catalysis promotion agents in the aq. biphasic hydroformylation of higher olefins. The property of surfactant and ligand can be assumed by the same molecule, e.g. di-sulfonated cetyl(diphenyl)phosphine 42. 1-Dodecene is hydroformylated in water/toluene (3 1) under mild conditions [olefin/Ru = 2500, CO/H2=1, P(CO + H2) = 15 bar, 42/Ru = 10] with TOF = 188 Another approach to... 

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