Tandem Reductive Hydroformylation of Castor Oil Derived Substrates and Catalyst Recycling by Selective Product Crystallization

Abstract

An orthogonalt andemc atalytic system consisting of rhodium and ruthenium complexes yieldedl inear C 12 a,w-bifunctional compounds from commercial, castor oil derived renewable substrates. With aldehyde yields up to 88 %a nd selectivities to the linear species of up to 95 %, this approachi sd irect and atom economic and provides easy access to potentialp olymer precursors for polycondensates. Additionally,astraightforward methodf or selective product crystallization was developed, which enabled recycling of the tandemc atalytic systemf or two runs with excellent activity and simultaneously provideda high-purity product.

Rhodium-Biphephos-Catalyzed Tandem Isomerization–Hydroformylation of Oleonitrile

“…In 2013, Nozaki and coworkers combined tandem isomerization-hydroformylation of methyl oleate with hydrogenation of the resulting aldehydes in alcohols for a high final l/b = 81:19 and yet 29% of direct alkene hydrogenation [25]. Very recently, Behr and coworkers developed an efficient combination of Pd and Rh catalysts to convert methyl oleate into the corresponding linear aldehydes: HPdBr(P(tBu)3)2 catalyzes the dynamic isomerization of the C=C bond and a Rh-Biphephos catalyst converts the terminal olefin into aldehydes with a l/b of up to 91:9 [26,27]. It is noteworthy that, in all of the above examples, harsh conditions as well as a long reaction time favor the desired isomerization-hydroformylation and also all side reactions, especially the hydrogenation of C=C bond(s) and the direct hydroformylation of internal alkenes.…”

Insights in the Rhodium-Catalyzed Tandem Isomerization-Hydroformylation of 10-Undecenitrile: Evidence for a Fast Isomerization Regime

“…5-Hexenenitrile was purchased from Aldrich Chemicals (St. Louis, MO, USA) and elution through a short neutral alumina column before use. 1 H, 13 C NMR and 31 P NMR spectra were recorded on Bruker AC-300 and AM-400 spectrometers (Bruker, Wissembourg, France). 1 H and 13 C chemical shifts were determined using residual signals of the deuterated solvents and were calibrated versus SiMe 4 .…”

“…Hence, to reach high selectivities and conversions toward the desired linear aldehyde, a tandem process is required, in which dynamic isomerization and (essentially) irreversible hydroformylation reactions must be effectively coupled [2,3]. This approach proved in several instances to be a synthetically quite effective strategy, through tuning of the catalyst system and optimizing the reaction conditions [4][5][6][7][8][9][10][11][12][13][14][15][16][17]. However, the fundamentals of this process such as detailed speciation of organic products over time, kinetics, were rarely investigated [11].…”

Dual Rh−Ru Catalysts for Reductive Hydroformylation of Olefins to Alcohols

“…However,t od ate few catalysts are known that promote the transformation of olefins directly into alcohols. [11] An important achievementw as reported by Nozaki and co-workersi n 2010, who described at andemh ydroformylation-hydrogenation of 1-decene to undecanol in > 90 %y ield by using ab imetallicc atalystc onsisting of Rh-Xantphos and Shvo's complex. [12] This complex is aw ell-known example of ah ydrogenation catalyst that operates by an outer-sphere mechanism.…”

“…[9] In this respect, combination of hydroformylation and reduction-so-called hydrohydroxymethylation-would allow forastraightforward and atom-efficient accesst oa lcohols directly from easily available olefins and syngas. [11] An important achievementw as reported by Nozaki and co-workersi n 2010, who described at andemh ydroformylation-hydrogenation of 1-decene to undecanol in > 90 %y ield by using ab imetallicc atalystc onsisting of Rh-Xantphos and Shvo's complex. [10] In principle, combining the isomerization of internal to terminal olefins, followed by nselectiveh ydroformylation and subsequent hydrogenation of the obtained aldehyde allows for an ideal synthesis of n-alcohols.…”