Abstract. The water soluble cobalt complex HCo(CO)[P(o-C6H4SO3Na)]3 was used as catalyst precursor for the biphasic aqueous hydroformylation of 1-hexene. The complex was synthesized by reductive carbonylation of CoCl2.6H2O in the presence of o-TPPTS ([P(o-C6H4SO3Na)]3) under nitrogen atmosphere and characterized by FTIR, 1H NMR and 31P {1H} NMR, 13C NMR, DEPT - 135, COSY, HSQC, MS (ESI). The catalytic activity of the complex in the biphasic hydroformylation reaction of 1-hexene was evaluated under moderate reaction conditions. The pressure and temperature were varied from 4137 - 7584 kPa (600-1100 psi) of syngas and from 353 - 383 K (80 - 110 oC), respectively. The 1-hexene concentration was varied from 0.021-0,11M and the catalyst from 4x10-4 - 1.1x10-3 M. The best conversion at 363 K and 7584 kPa and 7.5 h was 62% with selectivity towards aldehydes (heptanal and 2-methyl-hexanal) of 66% to with l/b ratio of 2.6. The recycling of the catalytic precursor after four successive times, did not show any loss on the activity, having selectivity towards aldehyde up to 60%.

Resumen. El complejo soluble en agua HCo(CO)[P(o-C6H4SO3Na)]3 fue usado como precursor catalítico para la hidroformilación de 1-hexeno. El complejo fue sintetizado por carbonilación reductiva de CoCl2.6H2O en presencia de o-TFFTS,([P(o-C6H4SO3Na)]3) en atmosfera de nitrógeno y caracterizado por IRFT 1H RMN y 31P {1H} RMN, 13C RMN, DEPT - 135, COSY, HSQC, MS (ESI). La actividad catalítica del complejo en la hidroformilación bifásica acuosa de1-hexeno fue evaluada bajo condiciones moderadas de reacción. La presión y la temperatura se variaron desde 4137 - 7584 kPa (600-1100 psi) de gas de síntesis y de 353 - 383 K (80 - 110 oC), respectivamente. La concentración de 1-hexeno se varió desde 0.021-0.11M y la del catalizador desde 4x10-4 - 1.1x10-3 M. La mejor conversión fue 62% a 363 K y 7584 kPa en 7.5 h con una selectividad de 66% hacia los aldehídos (heptanal y 2-metil-hexanal), obteniéndose y una relación n/i de 2.6. El precursor catalítico fue reciclado durante cuatro veces sucesivas sin mostrar perdida en la actividad catalítica y con una selectividad hacia aldehídos de 60 %.

Abstract. The reaction of alkenes (allyl alcohol, styrene and C6 alkenes) with formaldehyde was efficiently performed by using Rh precatalysts formed in situ by the addition of triphenylphosphine (PPh3), 1,2-bis(diphenylphosphino)ethane (dppe) or 1,1,1-tris(diphenylphosphinomethyl)ethane (triphos) to the complex Rh(acac)(CO)2 at 130ºC in 1,4-dioxane, yielding their corresponding aldehydes; the best catalytic system was Rh(acac)(CO)2/2dppe, which generates the cationic complex [Rh(κ2-P,P-dppe)2]+. However, the reaction of phenylacetylene with formaldehyde under the same reaction conditions generated styrene, which was found to be the product of transfer hydrogenation from formaldehyde.

Resumen. La reacción de alquenos (alcohol alílico, estireno y alquenos C6) con formaldehido se realizó eficientemente usando precatalizadores de Rh formados in situ por adición de trifenilfosfina (PPh3), 1,2-bis(difenilfosfino)etano (dffe) o 1,1,1-tris(difenilfosfinometil) etano (trifos) al complejo Rh(acac)(CO)2 a 130ºC en 1,4-dioxano, produciendo los correspondientes aldehídos. El mejor sistema catalítico fue Rh(acac)(CO)2/2dffe, el cual genera el complejo catiónico [Rh(κ2-P,P-dffe)2]+. Sin embargo, la reacción de fenilacetileno con formaldehido bajo las mismas condiciones de reacción generó estireno, el cual es el producto de la transferencia de hidrógeno del formaldehido.

The catalytic activity of systems of type [RuH(CO)(N-N)(PR3)2]+ was evaluated in the hydroformylation reaction of 1-hexene. The observed activity is explained through a reaction mechanism on the basis of the quantum theory. The mechanism included total energy calculations for each of the intermediaries of the elemental steps considered in the catalytic cycle. The deactivation of the catalyst precursors takes place via dissociation of the polypyridine ligand and the subsequent formation of thermodynamically stable species, such as RuH(CO)3(PPh3)2 and RuH3(CO)(PPh3)2, which interrupt the catalytic cycle. In addition, the theoretical study allows to explain the observed regioselectivity which is defined in two steps: (a) the hydride migration reaction with an anti-Markovnikov orientation to produce the alkyl-linear-complex (3.1a), which is more stable by 19.4 kJ/mol than the Markovnikov orientation (alkyl-branched-complex) (3.1b); (b) the carbon monoxide insertion step generates the carbonyl alkyl-linear specie (4.1a) which is more stable by 9.5 kJ/mol than the alternative species (4.1b), determining the preferred formation of heptanal in the hydroformylation of 1-hexene.

Um catalisador de ródio ancorado em uma resina de troca iônica comercial (IRA900/TPPMS/Rh) foi preparado de maneira direta, através de um protocolo simples, a partir de precursores prontamente disponíveis. O material foi usado como um catalisador heterogêneo para a hidroformilação e a sequência tandem hidroformilação/acetalização do eugenol e do estragol em condições brandas. A regiosseletividade para os produtos lineares foi cerca de 62%, mas para os alil benzenos os produtos ramificados são também valiosos. O desempenho do catalisador ancorado na hidroformilação foi comparável aos catalisadores homogêneos de ródio convencionais, entretanto, sua eficiência na etapa de acetalização foi significativamente mais elevada. O material pode ser separado da solução reacional por decantação e pode ser reutilizado sem perda significativa de atividade ou seletividade. Este método catalítico simples representa uma rota alternativa economicamente atrativa para compostos de valor comercial como fragrâncias partindo de substratos prontamente disponíveis de fontes bio-renováveis.

A rhodium catalyst anchored in a commercial anion exchange resin (IRA900/TPPMS/Rh) was prepared straightforwardly through a simple protocol from readily available precursors. The material was used as a heterogeneous catalyst for the hydroformylation and tandem sequence hydroformylation/acetalization of eugenol and estragole under mild conditions. The regioselectivity for linear products was ca. 62%, but for the allyl benzenes the branched isomer are also valuable. The performance of the anchored catalyst in hydroformylation was comparable to that of the conventional homogeneous rhodium system; however, its efficiency in the acetalization step was significantly higher. The material can be separated from the reaction solutions by decantation and re-used without a significant loss in activity and selectivity. This simple catalytic method represents an economically attractive route to commercially valuable fragrance compounds starting from the substrates easily available from natural bio-renewable sources.

In this work, we describe the hydroformylation of methyl oleate catalyzed by several rhodium complexes. Parameters including total pressure, phosphorous/rhodium and CO/H2 ratio, temperature and phosphorous ligands were scanned. Total conversion of the starting double bonds was achieved while maintaining excellent selectivity in aldehydes.

The thiols,1-phenylethanothiol 1 and 2,4-pentanodithiol 2 were synthesised and used to prepare binuclear rhodium species 3, 4 of the type [Rh2(µ-L)n(cod)2] (L = 1, n = 2; L = 2, n = 1; cod = 1,5cyclooctadiene). NMR and FAB+ mass spectrometry data are consistent with a binuclear structure for the species. These complexes, plus PPh3 or diphosphines (dppp, dppb), were used as catalytic precursors for the hydroformylation of styrene under mild conditions. Fairly good activities and regioselectivities were achieved for catalytic system 3/ PPh3.

Los tioles,1-feniletanotiol 1 and 2,4-pentanoditiol 2 fueron sintetizados y empleados para preparar especies binucleares de rodio 3, 4 de formulación [Rh2(µ-L)n(cod)2] (L = 1, n = 2; L = 2, n = 1; cod = 1,5-ciclooctadieno). Los espectros de RMN y espectrometría de masas FAB+ son consistentes con una estructura binuclear para estas especies. Estos complejos junto con Pф3 o difosfinas (dppp, dppb), fueron usados como precursores catalíticos en la hidroformilación de estireno en condiciones suaves de reacción. Con el sistema catalítico 3/Pф3 se alcanzaron buenas actividades y selectividades.

The catalysis of the hydroesterification and hydroformylation-acetalization of 1-hexene by rhodium(I), cis-[Rh(CO)2(amine)2](PF6) complexes (amine = pyridine, 2-picoline, 3-picoline, 4-picoline, 3,5-lutidine or 2,6-lutidine) dissolved in 10 mL of ethanol or 10 mL of 80% aqueous ethanol, 0.4 mL (3 x 10-3 mol) of 1-hexene, [Rh] = 5 x 10-5 mol, 1-hexene/Rh = 64 under P(CO) = 0.9 atm at 100 °C for 4 h, is described in this work. The mayor products are ethyl-heptanoate, heptanal and 1,1-diethoxyheptane coming from the hydroesterification, hydroformylation reactions and the nucleophilic addition reaction of the ethanol over the formed heptanal, respectively. The reaction product distribution depends on the nature of the coordinate amine to the rhodium center

Reações de hidroformilação foram realizadas com oleato de metila grau técnico e óleo de soja usando [RhH(CO)(PPh3)3] e [RhCl3.3H2O] (ligação dupla/Rh = 745) como precursores catalíticos, modificados ou não por trifenilfosfina. O complexo [RhH(CO)(PPh3)3] levou a 100% de conversão e 80-91% de produtos hidroformilados em 4 h para ambos substratos, sob condições reacionais brandas (100 ºC, 40 bar, CO/H2 = 2:1, ligante/Rh = 10:1). Verificou-se a rápida isomerização do óleo de soja, produzindo isomeros trans e dienos conjugados, porém sem prejuízo à hidroformilação. A reação do óleo de soja com [RhCl3.3H2O] puro, produz somente dienos conjugados, mas quando esse precursor foi modificado com trifenilfosfina (ligante/Rh = 10:1), nenhuma reação foi observada. Curiosamente, cristais amarelos correspondente ao complexo [Rh(Cl)(CO)(PPh3)2] foram quantitativamente isolados ao final da reação.

Hydroformylation experiments were performed with technical-grade methyl oleate (MO) and soybean oil (SO) using [RhH(CO)(PPh3)3] and [RhCl3.3H2O] (double bond/Rh = 745) as catalyst precursors modified or not by triphenylphosphine. [RhH(CO)(PPh3)3] shows 100% conversion and 80-91% selectivity to aldehydes in only 4h for both substrates under mild conditions (100 °C, 40 bar, CO/H2 = 2:1, ligand/Rh = 10:1). Despite the rapid isomerisation of the soybean oil, producing trans isomers and conjugated dienes, no effects were observed on its further conversion to aldehydes. The reaction of soybean oil conducted with pure [RhCl3.3H2O] produced only conjugated dienes, and when this precursor was modified with triphenylphosphine (ligand/Rh = 10:1) no reaction was observed at all. Curiously, yellow crystals corresponding to the complex [Rh(Cl)(CO)(PPh3)2] were quantitatively isolated at the end of the reaction .

Complexos de ródio preparados in situ a partir de [Rh(OMe)(COD)]2, [Rh(CO)2(acac)], [Rh(cod)(acac)] ou [Rh(cod)(PPh3)2]+BPh 4- com ligantes como HS(CH2)3Si(OMe)3, Ph2P(CH2)2S(CH 2)3Si(OMe)3 ou Ph2P(CH2)2Si(OMe) 3 foram imobilizados em matrizes de sílica, inorgânicas ou híbridas, pelo processo sol-gel. As matrizes inorgânicas foram preparadas apenas com tetrametilortossilicato enquanto que para as híbridas foram utilizados 1,4-bis(trietoxissilil)benzeno ou 1,2-bis(trietoxissilil)etano como agentes de co-condensação. O sistema baseado em [Rh(CO)2(acac)]/ Ph2P(CH2)2S(CH 2)3Si(OMe)3 foi ativo na hidroformilação de 1-hexeno e de 1-octadeceno sem lixiviação de ródio. Também pôde ser usado na ausência de solvente, como observado na hidroformilação do 1-deceno. Apesar do melhor sistema obtido apresentar uma matriz microporosa, não foi possível estabelecer uma correlação direta entre composição da matriz, grau de condensação da mesma e propriedades da superfície.

Rhodium complexes prepared in situ from [Rh(OMe)(COD)]2, [Rh(CO)2(acac)], [Rh(cod)(acac)] or [Rh(cod)(PPh3)2]+BPh 4- with ligands as HS(CH2)3Si(OMe)3, Ph2P(CH2)2S(CH 2)3Si(OMe)3 or Ph2P(CH2)2Si(OMe) 3 were immobilized in inorganic and hybrid silica matrices via the sol-gel process. The inorganic matrices were prepared with tetramethylorthosilicate while for the hybrid ones 1,4-bis(triethoxysilyl)benzene or 1,2-bis(triethoxysilyl)ethane were used as co-condensation agents. The system based on [Rh(CO)2(acac)]/ Ph2P(CH2)2S(CH 2)3Si(OMe)3 was active in the hydroformylation of 1-hexene and 1-octadecene without any rhodium leaching. It could also be used in the absence of a solvent, as observed in the hydroformylation of 1-decene. Although the best system was based on a hybrid microporous matrix, no straightforward correlation between matrix composition, condensation degree and surface properties could be found.

Reported here is the catalytic studies of the hydroformylation and the isomerization of 1-hexene to aldehydes (heptanal and 2-methyl-hexanal) and 2-hexene, respectively by [Rh(COD)(amine)2]PF6 complexes (COD = 1,5-cyclooctadiene, amine = 4-picoline, 2-picoline or 2,6-lutidine) immobilized on poly(4-vinylpyridine) in contact with 10 mL of 80% aqueous 2-ethoxyethanol, under CO atmosphere (0.9 atm at 100 C). The results of these studies show the following reactivity order defined as Turnover Frequencies for aldehydes production: 2-picoline {2.9} > 4-picoline {2.6} > 2,6-lutidine {2.4}. The electronics and steric effects induced by the amine ligands apparently influence on the observed catalytic activities. The [Rh(COD)(2-picoline)2]PF6/poly(4-vinylpyridine) system also catalyzed the hydroformylation and isomerization of 1-octene

In the present paper some general aspects of metal complex catalysis and its applications for oxyfunctionalization of various olefins, including naturally occurring ones, via selective oxidation, hydroformylation and alkoxycarbonylation are discussed.

Four silica samples were evaluated as supports in the hydroformylation of oct-1-ene by Supported Aqueous Phase Catalysis (SAPC) using [Rh2(µ-StBu)2(CO)2(TPPTS)2] and [Rh(COD)Cl]2/TPPTS as catalysts. Adsorption studies of the [Rh(COD)Cl]2/TPPTS complex from aqueous solutions on the supports were carried out at 25 °C. The isotherms obtained were correlated by several models, among which the Fowler-Guggenheim/Jovanovic-Freundlich equation was found to be the most satisfactory. The influence of the nature of catalytic complex and of the methods for supporting the catalyst on the silica conversion was also studied.

In the present work, we report the homogeneous catalytic hydroformylation reaction of formaldehyde with rhodium complexes like [Rh(CO)2L2](PF6) with L = pyridine (1) or 4-picoline (2), using different solvents such as toluene, acetone, N,N-dimethylformamide, and 4-picoline. The experiments were carried out in an autoclave (Parr, 100 mL), 10 atm, CO/H2 = 1 and ratio catalyst/substrate 1/100. Preliminary kinetics parameters show a high catalytic activity of these complexes to the formation of methanol and methyl formate

En el presente trabajo, reportamos la catálisis homogénea de la reacción de hidroformilación de formaldehído con complejos de rodio del tipo [Rh(CO)2L2](PF6) con L = piridina (1) o 4-picolina (2), utilizando diferentes solventes tales como tolueno, acetona, N,N-dimetilformamida y 4-picolina. Los experimentos fueron llevados a cabo en un autoclave (Parr, 100 mL), 10 atm, CO/H2 = 1, relación catalizador/sustrato 1/100. Parámetros cinéticos preliminares muestran una alta actividad catalítica de estos complejos, a la formación de metanol y formato de metilo

The hydroformylation reaction represents one of the most important C1-chemistry area in the chemical industry. This catalytic process, which has been developed up to now mainly to the production of commodities chemicals, has shown a remarkable potential for the preparation of several categories of specialty chemicals and in particular pharmaceutical compounds. Arylpropanoic acids, various amines containing aryl groups, and intermediates for the preparation of vitamins, carbocyclic and heterocyclic compounds and many other classes of organic molecules endowed with pharmacological activity are currently accessible in good-to-high yields through hydroformylation of selected olefinic substrates. The asymmetric hydroformylation is going to reach the stage of maturity and hence to contribute in solving many troublesome synthetic problems connected with the preparation of pharmacologically active compounds with very high enantiomeric purity. The present survey emphasizes the usefulness of synthesis gas as a starting material in fine chemistry, which is expected to be important for industry.