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An innovative bitopic phosphoramidite ligand L was proficiently synthesized and subsequently employed in coordination with two distinct metal species (AgI and RhI), leading to the construction of a heterometallic coordination polymer. The catalyst showcased remarkable performance in the hydroformylation of long-chain alkenes, displaying high activity and selectivity with a minimum yield of 90% for aldehydes. Operating as a heterogeneous catalyst, it not only demonstrated outstanding efficacy in facile separation from the product but also maintained a low rhodium loss per catalytic cycle. The catalyst exhibited exceptional stability, remaining high activity and selectivity over 10 successive reuses. Moreover, the RhAgL catalysts exhibit notable isomerization effects on alkenes, which promote the preferential formation of branched aldehydes in the resulting product. The straightforward synthetic strategy employed in preparing this highly effective catalyst introduced an innovative concept for heterogeneous catalysis, offering promising prospects for advancing industrial processes. This remarkable performance indicates the catalyst's potential for sustainable and efficient chemical transformations, highlighting its significance in driving advancements in catalytic technology for a variety of applications in industry. [ABSTRACT FROM AUTHOR]

A new rotationally hindered diphosphoramidite ligand has been applied to the Rh-catalyzed hydroformylation of various olefins. Good activity as well as excellent regioselectivity toward the formation of linear aldehydes were achieved. Remarkable performances were also observed in the hydroformylation of functionalized olefins, including methyl acrylate, allyl acetate, crotonaldehyde ethylene acetal and styrene. [ABSTRACT FROM AUTHOR]

Three bidentate phosphoramidite ligands were synthesized, characterized, and employed in Rh‐catalyzed hydroformylation of vinyl ethers. The complex Rh(acac)(2,2′‐bis{(di[1H‐indol‐1‐yl]phosphanyl)oxy}‐1,1′‐binaphthalene} (acac = acetylacetone) (Rh‐L4) was also synthesized and characterized. Rh‐L4 showed good regioselectivity for the hydroformylation of vinyl ethers under mild reaction conditions: 2 MPa of syngas, 1:1 (H2/CO) substrate/catalyst molar ratio 1000:1, and 60 °C. The linear selectivity was up to 98%, and in most cases was about 80%, with no hydrogenation product formation observed, which could be a potential way to synthesize 1,3‐propanediol. A mechanism study including density functional theory computational analysis showed that both Rh–H and CO insertion steps in the hydroformylation of vinyl ether were linear‐preferred in our catalyst system. [ABSTRACT FROM AUTHOR]

The application of polyethylene glycol (donated as PEG), as an environmentally benign solvent instead of water, in rhodium catalyzed hydroformylation of long chain alkenes by using water soluble phosphine BISBIS or TPPTS (TPPTS: sodium salt of sulfonated triphenylphosphine, BISBIS: sodium salt of sulfonated 2,2′-bis(diphenylphosphinomethyl)-1,1′-biphenyl) is herein reported. The conversion of long chain alkenes in PEG-200 could reach above 95.0% after a short reaction time (15 min). In addition, an efficient phase separation and recycling of PEG-200 and catalyst were achieved. The leaching of rhodium into product phase detected by ICP-AES was less than 0.06 wt% of the initial amount. Graphical Abstract: [ABSTRACT FROM AUTHOR]

The organic/aqueous biphasic of 2,5-norbornadiene (NBD) was investigated for the first time using HRh(CO)(TPPTS)3 (TPPTS: trisodium salt of tri( m-sulphonylphenyl)phosphine) as the catalyst precursor. A comparison was made of homogeneous and biphasic systems. The optimum reaction parameters are discussed and the reaction mechanism is presented. In order to ensure the process attained high activity under moderate conditions, the effect of various cationic surfactants was tested in the biphasic of NBD. The results indicated that the of NBD in the biphasic system exhibited high activity and high selectivity to dialdehyde products under mild conditions. The addition of cationic surfactants markedly accelerated the reaction. A single long-chain surfactant seemed to exert a greater impact on the of NBD than a double long-chain surfactant. Moreover, the recycling of aqueous solution containing catalyst with or without surfactant was investigated. In the absence of the surfactant, the aqueous catalyst could be recycled six times without a significant decrease in activity and selectivity. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

[Display omitted] • A series of new and easily tunable diphosphine ligands have been synthesized. • Product selectivity in hydroformylation of strained dialkenes can be controlled. • Coordination modes of Rh complexes bearing the new ligand are analyzed. • Ligand effects on product selectivity and complex coordination modes are mentioned. We reported the synthesis of new and easily tunable diphosphine ligands L1 - L5 based on bis(1H-indol-3-yl)methane. Strained 2,5-norbornadiene and dicyclopentadiene were used as the substrates to elucidate the relationship between ligand structure and product selectivity in Rh-catalyzed hydroformylation. Details in NMR, HRMS and single-crystal X-ray diffraction revealed that the coordination number and oxidation state could change rapidly upon exposure of RhI- L complexes to air. More importantly, the special structure of ligand which led to intramolecular methylene C–H oxidative addition to metal center could facilitate the hydroformylation reaction in an unexpected way. [ABSTRACT FROM AUTHOR]

Abstract: The preparation of a new surface-active sulfonated phosphine and its catalytic performance in aqueous biphasic hydroformylation of long chain olefins were reported. The amphiphilic phosphine: sodium salt of sulfonated n-C12H25O C6H4P(C6H4-p-CH3O)2 (DMOPPS) was prepared by sulfonation of the hydrophobic phosphine DMOPP in concentrated H2SO4 under N2 atmosphere at 30°C for about 5h. The rhodium complex, RhCl(CO)(TPPTS)2 [TPPTS=P(C6H4-m-SO3Na)3], was used as the catalyst precursor. The catalytic active species with the DMOPPS as ligand was in situ formed by adding DMOPPS to the RhCl(CO)(TPPTS)2 catalyst precursor. The surface-activity and micelle-forming property of this new amphiphilic phosphine were confirmed by using cryogenic transmission electron microscope (Cryo-TEM). Under the same conditions, the biphasic hydroformylation of 1-decene using DMOPPS as ligand was compared with that using traditional TPPTS as ligand. The catalysis system using DMOPPS was also compared with the previous Rh-TPPTS-surfactant [C12H25N(CH3)3I (DTAI)] system. Some reaction parameters such as stirring rates, alkyl chain length of olefins, the molar ratio of phosphine/rhodium, and the catalyst recycle were also studied in detail. The results showed that the ligand DMOPPS exhibited a micelle-forming property that could significantly enhance the hydroformylation reaction rate of long chain olefin. Moreover, the surface-active phosphine may also stabilize the aqueous/oil phase boundary, which could enhance the biphasic catalytic reaction rates. [Copyright &y& Elsevier]

Abstract: A series of new triarylphosphine ligands with long-chain alkoxy group, [m-MeOC6H4P(p-CH3(CH2) n OC6H4)2 and m-MeOC6H4P(m-CH3(CH2) n OC6H4)2, n =0, 3, 7, 11 and 15], have been synthesized by a novel method. These phosphines with different electron-donating substituent were applied as ligands in rhodium-catalyzed hydroformylation of styrene. The results indicated that the longer-chain-length of p-alkoxy group was favorable to the formation of 2-phenylpropanal, but increasing the chain-length of m-alkoxy group decreased the selectivity for the 2-phenylpropanal. [Copyright &y& Elsevier]

Abstract: Six cationic gemini and trimeric surfactants: N,N′-didodecyl-N,N′-dimethyl piperazinium iodide (2), the monooxlate of N,N′-didodecylpiperazine (3), the hydrochloride of N,N′-didodecylpiperazine (4), the 1,3,5-trimethyl-1,3,5-tridodecylhexahydro-1,3,5-trazinium iodide (5), the monooxlate of 1,3,5-tridodecylhexahydro-1,3,5-triazine (6) and the hydrochloride of 1,3,5-tridodecylhexahydro-1,3,5-triazine (7) were prepared using the regular methods. These cationic surfactants and a double-chained surfactant, didodecyldimethylammonium bromide (1), were successfully applied as catalysis promotion agents in aqueous biphasic hydroformylation of higher olefins. The aqueous catalysts used in present study were RhCl(CO)(TPPTS)2–TPPTS [TPPTS: P(m-C6H4SO3Na)3]. The experimental results showed that while all these cationic surfactants could accelerate the hydroformylation reaction, surfactants 1, 2, 6, 7 exhibited more significant promotion effects. The influences of the surfactant anions on the reaction were also discussed. Of the three gemini surfactants 2, 3, and 4, which were derived from N,N′-didodecylpiperazine, surfactant 2 with iodide as anion exhibited substantially higher promotion effect than surfactants 3 with monooxalate and 4 with chloride as anion, respectively. On the other hand, among the three trimeric surfactants 5, 6, 7, which were derived from 1,3,5-tridodecylhexahydro-1,3,5-triazine, surfactants 6 with monooxalate and 7 with hydrochloride as anion displayed better acceleration effect than surfactant 5 with iodide as anion. Compared with the double-chained and single headed surfactant 1, surfactant 2 containing two alkyl chains and cationic heads and surfactant 6 with three alkyl chains and cationic heads were superior additives to accelerate the hydroformylation reactions. When they were used as catalysis promotion additives, less water-soluble phosphine (TPPTS) was required to immobilize the rhodium catalyst in aqueous phase, and the hydroformylation reaction proceeded more regioselectively toward the valuable linear aldehyde under lower syngas pressure. [Copyright &y& Elsevier]

Abstract: The double long-chain cationic surfactants (DLCS) were used in higher olefin hydroformylation catalyzed by water-soluble rhodium catalyst in aqueous/organic biphasic system. The reaction rate was greatly accelerated and the value of TOF (turn over frequency defined as the moles of converted olefin per mole Rh per hour) in 1-dodecene hydroformylation could achieve 2291h−1 even without stirring. When the reaction was carried out with stirring rate of 400rpm, TOF increased to 7472h−1. These values of TOF were comparable with that in homogeneous catalysis system. The phenomenon is attributed to the formation of vesicle and the enrichment of rhodium catalyst in the interfacial layer, as well as the high transfer rate of olefins from the organic phase to the interface of vesicle. The acceleration mechanism of DLCS in biphasic catalysis was discussed. [Copyright &y& Elsevier]

Abstract: The promotional effect of cationic gemini surfactants for the hydroformylation of 1-dodecene in the organic/aqueous biphasic catalytic system is reported. Cationic gemini surfactants with a flexible spacer (G(Eth), G(But) and G(Hex)) and rigid spacer (G(Xyl)) group were used in the reaction. The critical micelle concentration (CMC) and solubilization of laurylbenzene in gemini surfactant solutions were determined. The influence of the concentration of gemini surfactants and the stirring rate on 1-dodecene hydroformylation were investigated. The reaction results showed that in the biphasic catalytic system the hydroformylation of 1-dodecene catalyzed by RhCl(CO)(TPPTS)2–TPPTS [TPPTS=tris(sodium-m-sulfonatophenyl) phosphine] in the presence of gemini surfactants occurred with higher turn over frequency (TOF) and higher regioselectivity toward linear aldehyde (L/B) than those obtained with the conventional monomeric surfactant CTAB. The phenomena could be attributed to the fact that the gemini surfactant has lower CMC and better surface tension reduction ability; moreover it could form more compact and spherocylindrical micelle in the solution. These properties would be favorable for the decrease in the phase transfer energy barrier, thereby greatly accelerating the reaction rate. Meanwhile, the more compact structure of the spherocylindrical micelle formed from gemini surfactant could construct a favorable microenvironment for the formation of linear aldehyde. The comparison of the acceleration effect of the three type surfactants (monomeric surfactant CTAB (cetyltrimethylammonium bromide), gemini surfactant G(Eth), G(But), G(Hex)), G(Xyl) as well as double chain surfactant DCMAB (di(cetylmethyl)ammonium bromide) indicated that the surfactant structure had an important effect on the reaction rate. Their promotion order is DCMAB>G(Eth)≈G(But)≈G(Hex)≈G(Xyl)>CTAB. [Copyright &y& Elsevier]

Tetraphosphine and bisphosphine ligands were synthesized, characterized and employed in Rh‐catalyzed hydroformylation of 1‐octene and 1‐hexene. Conversion of over 97.7% and aldehyde yield of 94.1% were achieved at 60°C, 20 bar. This remarkable performance could also be retained at lower temperature (i.e. 40°C) by prolonging the reaction time. The tetraphosphine ligand‐modified Rh catalyst could be reused for at least seven successive runs with catalytic activity and selectivity almost unchanged; the catalyst was separated from the products and recycled directly in homogeneous hydroformylation, indicating that the catalyst might have good stability. 31P NMR and high‐resolution mass spectral characterization hinted that the reason for the reusability of the catalyst might be that the tetraphosphine ligand is relatively air‐stable and is probably slowly oxidized during the recycling runs. The tetraphosphine ligand has four phosphorus atoms to be partially oxidized and could still coordinate with the Rh center via the unoxidized phosphorus atoms to stabilize the catalyst, based on the multiple chelating modes of the tetraphosphine ligand. Hence, the catalytic activity and selectivity could be retained for a certain number of runs. A new air‐stable tetraphosphine ligand‐based catalyst could lead to high conversion (>97.7%) and high aldehyde selectivity (>94.1%) at low temperature (40–60°C). Moreover, the tetraphosphine ligand could chelate with Rh due to the multiple chelating modes even though one or two phosphorus atoms were oxidized, providing at least seven reuses of the catalyst in homogeneous hydroformylation. [ABSTRACT FROM AUTHOR]

Abstract: The biphasic hydroformylation of higher olefins was performed efficiently in the halogen-free ionic liquids 1-n-alkyl-3-methylimidazolium p-toluenesulfonate ([Rmim][p-CH3C6H4SO3]) using Rh-TPPTS [TPPTS: trisodium salt of tri(m-sulphonylphenyl)phosphine] complexes as catalyst. The catalytic system offers high activity and chemoselectivity for aldehyde with a good retention of the catalyst in ionic liquid phase. The ionic liquid containing catalyst can be easily separated and reused several times without a significant decrease in the activity and selectivity. The results indicated that the cation and anion of ionic liquids strongly influenced the reaction rate. Furthermore, the reaction rate was markedly accelerated when the chain-length of alkyl in ionic liquids was comparable with that of olefin. A “matching effect” between the chain-length of alkyl in ionic liquids and that of olefins was firstly reported. [Copyright &y& Elsevier]

• The linear selectivity of valeraldehyde was over 99% with the yield of more than 93%. • Diphosphoramidite ligand is water and air stable, proved by hydrolysis, oxidation experiments and cyclic voltammetry measurements. • Diphosphoramidite ligand coordination to rhodium as ee configuration was confirmed by NMR and IR. • The Rh/diphosphoramidite catalyst could work well for beyond 40 h. Highly selective isomerization-hydroformylation of 2-butene was achieved with the presence of Rh(acac)(CO) 2 and a phosphoramidite bidentate ligand which bearing 2,2′-dihydroxy-1,1′-binaphthyl backbone and N-indolyl substitute. The molar ratio of n- to isovaleraldehyde (217) is distinctly higher than the reported systems. NMR and IR revealed that the five-coordinate HRh(ligand)(CO) 2 was an equatorial-equatorial configuration which contributed to the n-selectivity of valeraldehyde. The strong π-acceptor ability of ligand was suggested to play a key role in fast isomerization of 2-butene. Hydrolysis and oxidation experiments demonstrated that the ligand was water- and air-stable. Cyclic voltammetry measurement confirmed that this phosphoramidite ligand is more difficult to be oxidized, compared with the phosphine, phosphinite and phosphite ligands. Inspiringly, recycling experiments showed the catalytic system could work for at least 7 runs with unchanged selectivity. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Non-aqueous biphasic hydroformylation for higher olefins based on formamide was evaluated. • This system shows good activity and aldehyde chemoselectivity under mild condition. • Rhodium could be recycled for at least 40 times, with an average loss of 0.02 wt% for each run. • This system was successfully applied to crude Fischer-Tropsch synthesis higher α-olefins. A simple and recyclable biphasic rhodium catalytic system for the hydroformylation of long-chain alkenes is performed with the presence of Rh/TPPTS (trisodium tris(m-sulfophenyl)phosphine) in highly polar formamide for the first time. This work investigated the phase behavior of 1-octene, 1-nonanal and formamide, as well as the factors affecting the catalytic performance and catalyst recovery. Two phases were fully separated with distinct interface, allowing facile recycle of catalyst-containing formamide solution by decantation. Hydroformylation could be carried out under mild condition with turnover frequency and aldehyde selectivity up to 950 h−1 and 97 %, respectively. The catalyst could be reused for at least 40 runs without obvious activity and selectivity decline. No extra rhodium or TPPTS was needed during the cycle runs, and the average rhodium loss for each cycle was as low as 0.02 wt%. This system has also been successfully applied to the hydroformylation of crude higher α-olefins with high conversion and rhodium reservation, which were just distilled from Fischer-Tropsch synthesis with 64.7∼81.0 % fraction. [ABSTRACT FROM AUTHOR]