Dicyclopentadiene hydroformylation

In another interesting area in the study of hydroformylation, Davis developed the concept of supported aqueous phase (SAP) catalysis.175 A thin, aqueous film containing a water-soluble catalyst adheres to silica gel with a high surface area. The reaction occurs at the liquid-liquid interface. Through SAP catalysis, the hydroformylation of very hydrophobic alkenes, such as octene or dicyclopentadiene, is possible with the water-soluble catalyst [HRh(CO)(tppts)3]. 

Dicyclopentadiene has produced some interesting results. With rhodium catalyst at 115°C in tetrahydrofuran (THF), the dialdehyde was produced in good yield at 180°C that reaction proceeds further to form the diol in 67% yield (67). With a rhodium catalyst modified by excess triphenyl phosphite, the unsaturated monoaldehyde was obtained in a rapid reaction under very mild conditions (68, 69). The nonstrained 5-membered ring olefin required more strenuous conditions for hydroformylation. Either compound could be obtained in good yield by proper choice of conditions. 

Because the norbomene double bond of dicyclopentadiene is more strained, its selective hydrofbrmyl-ation can be achieved under mild reaction conditions (entry 9). Under more vigorous reaction conditions both double bonds are hydroformylated. The exo faces of both rings are the least hindered, accounting for the selectivity. 

Tricyclodecane dialdehyde (TCD-dial) the starting product for TCD-diamine, is formed by hydroformylation of dicyclopentadiene, DCP. This hydroformylation was used as a test reaction for re-immobilized catalysts in membrane techniques (eq. (6)). 

Reaction conditions feed, reaction product of hydroformylation of dicyclopentadiene solvent = about 50% toluene phosphorus source = TPPTS, 0.33 mol/mol amine pressure = 27 MPa Rh cone. = 60 ppm P/Rh ratio = 100 reaction temp. = 130 °C reaction time = 4 h. 

Tab. 3 Hydroformylation of dicyclopentadiene and membrane separation of the catalyst system (with variation of amines). 

Membrane separation conditions feed, reaction product of hydroformylation of dicyclopentadiene solvent, about 50% toluene membrane, UF-PA-5/PET 100 from the former Hoechst AG overflow, se 200 Lfr1 separation temperature, 40°C pretreatment of membranes in water at 80°C for 10 min transmembrane pressure, 10 bar. 

For ultrafiltration as a unit operation for the separation of polymer-bound soluble catalysts in particular, the recovery process for a rhodium catalyst from the hydroformylation of dicyclopentadiene is an illustrative example (for another detailed example, see Section 7.5) [26, 27]. Toluene can be used as a solvent with the polyaramide membrane employed. TPPTS or also a sulfonated bidentate phosphine with large ammonium counterions, are used as ligands. For efficient recovery, molecular weights of the catalyst of more than 3000 g mofi were required on the membrane used. Separation is performed in two steps [28]. A pilot plant was run successfully over an extended period of time of three months. 

Our work at Dow has also sought to examine the commercial viability of Rh/10, 11, 12 catalysts for the hydroformylation of a variety of olefins (33). The results that follow were obtained during laboratory and pilot plant studies on the hydroformylation of dicyclopentadiene (DCPD) to dicyclopentadiene dimethanol(DCPDDM) using various Rh carbonyl sources immobilized on 10, 11, and 12. 

As illustrated by the example of dicyclopentadiene, non-conjugated double bonds can be hydroformylated like isolated olefins, but rapid conjugation prior to the hydroformylation may prevent the formation of the expected poly-aldehydes. In the hydroformylation of 1,5-cyclooctadiene with unmodified Co or Rh catalysts, the main product was formyl cyclooctane [88]. In contrast, cycloheptatriene was formylated twice. The amount of triformylcycloheptanes did not exceed 10%. 

Hydroformylation of 2,6-ea o-tricyclo[5.2.1.0. ]dec-8-ene afforded preferentially the ea o-aldehyde (vertral = melon carboxaldehyde) (Scheme 6.17) [88]. Alternatively, it could be obtained in the same diastereomeric ratio by selective hydroformylation of 2,6-ex o-dicyclopentadiene and final hydrogenation on a Pd/C catalyst. If necessary, the isomers can be separated via their bisulfite... 

Hydroformylation of dicyclopentadiene, which is an important component of the Cg-fraction of the steam cracker [105], led to a mixture of isomeric diformyl-tricyclo[5.2.1.0 ]decanes (Scheme 6.28) [106, 107]. The compounds show a distinct spruce flavor. In fragrance application, they are characterized by a good adhesive strength and charisma. 

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