29189-87-5

Upstream product

• 30513-14-5 {Rh-bis(1,2-bis(diphenylphosphino)ethane))}ClO₄ 
• 253185-03-4 tert-butylbenzene 
• 125979-15-9 [(COD)Rh(μ-,kappa.O,O'-HCO2)]2 
• 1663-45-2 1,2-bis-(diphenylphosphino)ethane 
• 18284-36-1 hydridotetakis(triphenylphosphine)rhodium(I) 
• 188970-74-3 Mg⁽²⁺⁾*Cl^(1-)*Rh((C₆H₅)2PCH₂CH₂P(C₆H₅)2)2^(1-)=[Rh((C₆H₅)2PCH₂CH₂P(C₆H₅)2)2]MgCl 
• 64-17-5 ethanol 

Downstream Products

• 15043-47-7 [Rh(bis(diphenyl)phosphinoethane)₂][Cl] 
• 188970-76-5 Rh((C₆H₅)2PCH₂CH₂P(C₆H₅)2)2(CH₃) 
• 106223-53-4 Rh{(((C₆H₅)2P)2C₂H₄)2}⁽¹⁺⁾*CH₃C₆H₄SO₃^(1-) = Rh{(((C₆H₅)2P)2C₂H₄)2}(CH₃C₆H₄SO₃) 

Relevant academic research and scientific papers

TOLUENE-SOLVATED RHODIUM ATOMS: EVIDENCE FOR A HYDRIDORHODIUM COMPLEX

The codeposition of rhodium with toluene affords on melting a red brown solution, stable up to -50 deg C, which contains a hydridorhodium product, as shown by (1)H NMR analysis and isolation of hydrido complexes by reaction with phosphines.

Understanding the Relationship between Kinetics and Thermodynamics in CO2 Hydrogenation Catalysis

Catalysts that are able to reduce carbon dioxide under mild conditions are highly sought after for storage of renewable energy in the form of a chemical fuel. This study describes a systematic kinetic and thermodynamic study of a series of cobalt and rhodium bis(diphosphine) complexes that are capable of hydrogenating carbon dioxide to formate under ambient temperature and pressure. Catalytic CO2 hydrogenation was studied under 1.8 and 20 atm of pressure (1:1 CO2/H2) at room temperature in tetrahydrofuran with turnover frequencies (TOF) ranging from 20 to 74000 h-1. The catalysis was followed by 1H and 31P NMR spectroscopy in real time under all conditions to yield information about the rate-determining step. The cobalt catalysts displayed a rate-determining step of hydride transfer to CO2, while the hydrogen addition and/or deprotonation steps were rate limiting for the rhodium catalysts. Thermodynamic analysis of the complexes provided information on the driving force for each step of catalysis in terms of the catalyst hydricity (G°H), acidity (pKa), and free energy for H2 addition (G°H2). Linear free-energy relationships were identified that link the kinetic activity for catalytic hydrogenation of CO2 to formate with the thermodynamic driving force for the rate-limiting steps of catalysis. The catalyst exhibiting the highest activity, Co(dmpe)2H, was found to have hydride transfer and hydrogen addition steps that were each downhill by approximately 6 to 7 kcal mol-1, and the deprotonation step was thermoneutral. This indicates the fastest catalysts are the ones that most efficiently balance the free energy relationships of every step in the catalytic cycle.

Synthesis of thiiranes by rhodium-catalyzed sulfur addition reaction to reactive alkenes

A rhodium complex derived from RhH(PPh3)4, dppe, and 4-ethynyltoluene catalyzes the addition reaction of sulfur to norbornenes giving the corresponding thiiranes under acetone reflux conditions. The rhodium complex effectively transfers a sulfur atom to the double bond from sulfur, and exo-adducts are obtained. The reaction is also applicable to (E)-cyclooctene and cyclic allenes. The ring-opening reaction of the thiiranes with lithium aluminium hydride gives the corresponding thiols. This journal is

'Grignard-analogous' rhodium phosphane complexes

Interesting stoichiometric and catalytic reactions are possible with the rhodium phosphane complexes [{Ph2P(CH2)(n)PPh2)(n)}2Rh][MgC1] (1: a, n = 2; b, n = 3), which are readily accessible by reaction of the chloride complexes 2 with active magnesium. The 'Grignard-analogous' compounds 1 react to form 3 (E = H, Me SiMe3) by protolysis, alkylation, and silylation. The interconversion of complexes 2a and 1a can be used for catalytic transfer of two electrons from magnesium to CO2 to yield CO and CO3/2+.

Structure and reactivity of dimeric rhodium(i) formate complexes: X-ray crystal structure analysis of [{(cod)rh(μ-κ2o,o′-hco2)}2] and phosphane-induced hydride transfer to give an η3-cyclooctenyl complex

The X-ray crystal structure analysis of [(L2)Rh(μ-κ2O,O′-HCO2)2Rh(L′2)] 1a (L2 = L′2 = cod) is reported. Complex 1a reacts with CO to form 1c (L = L′ = CO) via the intermediate 1b (L2 = cod, L′ = CO). 1a and 1c do not incorporate 13CO2 or D2 in the formate moiety and are poor catalysts for CO2 hydrogenation to formic acid. Reaction of la with the chelating phosphanes R2P(CH2)2PR2 (R = Ph, iPr, Cy) 3a-c leads to replacement of the diolefin ligand and cleavage of the dimeric structure under formation of monomeric complexes [(3a-c)2Rh][HCO2] 4a-c. 4a was isolated in up to 78% yield and complexes [(3a)2RhH] 5a and [(3a)Rh(η3-C8H13)] 6a were detected as side products. Complexes of type 6 are formed exclusively under identical reaction conditions using the bidentate ligand Ph2P(CH2)3PPh2 3d or monodentate ligands PAr3 3e-f. A possible mechanism for the formation of complexes 4, 5 and 6 is discussed involving hydride transfer from the HCO-2 ligand to Rh and subsequently to coordinated cod.

Reaction of carbon monoxide with hydridobis[di(tertiary phosphine)]rhodium(I) complexes. Synthesis and structure of the metal-metal bonded carbonyl-bridged dimers [Rh(CO)(diphosphine)]2(μ-CO)2

Reaction of the hydridorhodium(I) complexes RhH(P-P)2 with carbon monoxide leads to formation of the dimeric carbonyl-bridged complexes [Rh(CO)(P-P)]2(μ-CO)2 with concomitant elimination of hydrogen, where P-P represents the di(tertiary phosphines): 1,2-bis(diphenylphosphino)ethane, 1,3-bis(diphenylphosphino)propane, and 2,3-O-isopropylidene-2,3-dihydroxy-1,4-bis(diphenylphosphino)butane, abbreviated as dppe, dppp, and diop, respectively. The Rh2(dppp)2(CO)4·1/ 2C6H6 complex exists as two crystallographically independent binuclear molecules possessing approximate C2 symmetry (triclinic, space group P1, a = 17.222 (3) A?, b = 21.513 (4) A?, c = 15.479 (3) A?; α = 90.929 (11)°, β = 108.358 (9)°, γ = 86.303 (12)°; Z = 4; R = 0.047 and Rw = 0.056 for 8068 reflections with I ≥ 3σ(I)). The structure is described in terms of two square pyramids (with phosphorus apical) sharing an edge formed by the two bridging carbonyl ligands, the mean angle between basal planes being 82.6°; a formal metal-metal single bond is indicated. Important bond lengths are Rh-Rh = 2.725 (1) and 2.709 (1) A?, Rh-P(basal) = 2.340 (3)-2.399 (3) A?, Rh-P(apical) = 2.316 (3)-2.340 (3) A?, Rh-CO(bridging) = 2.036 (9)-2.067 (10) A?, and Rh-CO(terminal) = 1.920 (11)-1.944 (11) A?. Low-temperature 31P{H} NMR spectra are consistent with the rigid structure; at room temperature the pairs of phosphorus atoms become chemically equivalent, probably via carbonyl site exchange since the 13C NMR spectrum is a single, broad resonance. Spectroscopic data for all three complexes indicate the same structure in each case. Like the corresponding bis(triphenylphosphine) species, the complexes are active catalysts for hydrogenation, isomerization, and hydroformylation of terminal olefins.