||||||||||||||| US005135901A United States Patent (19) (11) Patent Number: 5,135,901 Beavers 45) Date of Patent: Aug. 4, 1992

(54) A CATALYST COMPOSITION COMPRISING (56) References Cited RHODIUM, RUTHENIUMAND A PROMOTER U.S. PATENT DOCUMENTS 3,687,981 8/1972 Lawrence et al...... 549/372 (75) Inventor: William A. Beavers, Longview, Tex. 4,193,942 3/1980 Gerritsen et al...... 502/166 X (73) Assignee: Eastman Chemical Company, 4,453,019 6/1984 Chang ...... 502/166 X Rochester, N.Y. 4,668,651 3/1987 Billig et al. ... 502/161 X 4,719, 145 l/1988 Neely ...... 502/325 X (21) Appl. No.: 711,771 Primary Examiner-W. J. Shine (22) Filed: Jun. 7, 1991 Assistant Examiner-Douglas J. McGinty Attorney, Agent, or Firm-Mark A. Montgomery; Related U.S. Application Data William P. Heath, Jr.; S. E. Reiter 62) Division of Ser. No. 568,150, Aug. 16, 1990, Pat. No. 5,043,480, which is a division of Ser. No. 372,797, Jun. (57) ABSTRACT 29, 1989, Pat. No. 4,973,741. A catalyst used in a process for producing a 3-hydrox (51) Int. Cl...... B01J 23/64; B01J 27/185; yester product or a 3-hydroxyaldehyde product from B01J 27/24; B01J 23/46 ethylene oxide, carbon monoxide, and, optionally, hy (52) U.S. Cl...... 502/161; 502/162; drogen, is disclosed. This process uses, as a catalyst, a 502/325; 502/200, 502/213; 502/230; 502/201; catalyst comprising rhodium, ruthenium, and a Group 502/217; 502/170, 502/167; 502/233; 502/166 Va promoter. (58) Field of Search ...... 502/325, 200, 213, 230, 502/201, 217, 170, 161, 167, 162,233, 166 4 Claims, No Drawings 5,135,901 1. 2 and acrylates suitable for inclusion in any number of A CATALYST COMPOSITION COMPRISING solvents, resins, and plastics. RHODIUM, RUTHENIUMAND A PROMOTER The invention method is based on the carbonylation of ethylene oxide to g-hydroxypropionic acid deriva This is a divisional of copending application Ser. No. 5 tives, and optionally dehydrating the intermediate into 07/568,150 filed Aug. 16, 1990, now U.S. Pat. No. acrylic acid derivatives. By selecting different alcohol 5,043,480 which is a divisional of Ser. No. 372,797 filed functionalities to make the g-hydroxypropionic acid Jun. 29, 1989 now U.S. Pat. No. 4,973,741 issued Nov. derivatives, the properties of these final products can be 27, 1990. modified, 10 This invention encompasses a general method for BACKGROUND OF THE INVENTION producing difunctional compounds which have applica 1. Field of the Invention tions in such diverse areas as solvents, resins, coatings, The present invention relates to the production of and plastics. The catalyst system described herein is p-hydroxyesters or 6-hydroxyaldehydes from ethylene both versatile and more active than prior art catalysts oxide and synthesis gas. 15 known for these reactions. One basic catalyst formula 2. Discussion of the Background tion can be used for carbonylation, hydroformylation, The hydroformylation of ethylene oxide over cobalt or homologation giving good yields of each type of catalysts has been known for some time to yield g reaction product. hydroxyaldehydes (see, e.g., "Organic Syntheses Via It has been discovered that a catalyst comprising the Metal Carbonyls," I. Wender and P. Pino (1968), John 20 metals rhodium and ruthenium along with a Group Va Wiley and Sons, Inc., pp. 384-388; "Carbon Monoxide promoter is capable of converting ethylene oxide into in Organic Synthesis;" J. Falbe, (1970), Springer-Ver useful compounds having a three-carbon chain. Carry lag, pp 58-59). A major problem with this reaction, ing out the reaction under different reaction conditions however, is that it only provides low yields of alde will produce different products in good selectivities hydes. Attempting to increase yield of aldehydes using 25 Depending on the conditions selected, the main prod more forcing reaction conditions or longer reaction ucts obtained are f3-hydroxyesters or g-hydroxyalde times produces aldol condensation products instead of hydes. The conditions under which each of these prod the desired aldehyde products. ucts are predominantly formed is described in greater Rhodium is not known to catalyze the hydroformyla detail below. tion of ethylene oxide. It is known that rhodium pro 30 motes the carbonylation of ethylene oxide to produce DETAILED DESCRIPTION OF THE B-lactones (see "Homogeneous Catalysis with Com INVENTION pounds of Rhodium and Iridium," by R. S. Dickson; D. The catalyst composition provided by the present Reidel Publishing House, 1985). invention comprises (1) 100 parts of a rhodium compo It is also known to promote the carbonylative ring 35 nent, (ii) 0.1 to 10 parts of a ruthenium component, and opening of ethylene oxide in the presence of alcohols to (iii) 10 to 10 parts of a promoter component. The rho yield 3-hydroxypropionate esters as disclosed, for ex dium component is a rhodium salt or a rhodium com ample, by Kawabata et al. in Nippon Kagaku Kaishi, plex. The ruthenium component is a soluble homoge 635 (1979). These authors disclose the use of dicobalt nous ruthenium compound or a finely divided ruthe octacarbonyl/pyridine catalysts. The resulting prod nium metal. The promoter component is a nitrogen ucts, at present, have limited utility, being used for the containing compound, a phosphorus-containing com preparation of acrylate esters which in turn can be used pound, an arsenic-containing compound, or an antimo for the preparation of acrylate resins and polyesters. iny-containing compound. There is thus a distinct need for a process for readily The process for preparing a g-hydroxyproponate producing useful products from ethylene oxide 45 ester provided by the invention comprises contacting synthesis gas, ethylene oxide, a primary C1-6 alkyl alco OBJECTS OF THE INVENTION hol or benzyl alcohol, and a catalyst at a temperature . Accordingly, one object of this invention is to pro from 40 C. to 120° C.; wherein the catalyst comprises vide a novel process for producing a 3-hydroxyester rhodium, ruthenium, and a group Va promoter, and product from ethylene oxide, carbon monoxide, hydro 50 wherein the synthesis gas has a hydrogen to carbon gen, and a primary alcohol. monoxide molar ratio of from 0 to 0.5. It is another object of this invention to provide a The process for preparing a £3-hydroxypropionalde novel process for producing a g-hydroxyaldehyde hyde (or its dimer, 2013-hydroxyethyl)-4-hydroxy-1,3- product from ethylene oxide, carbon monoxide, and dioxane) provided by the present invention comprises hydrogen. 55 contacting synthesis gas, ethylene oxide, and a catalyst It is another object of this invention to provide a at a temperature of from 50' C. to 130' C.; wherein the novel catalyst composition useful for catalyzing the catalyst comprises rhodium, ruthenium, and a Group transformation of ethylene oxide, carbon monoxide, and Va promoter, and wherein the synthesis gas has a hy hydrogen into useful products. drogen to carbon monoxide molar ratio of from 0.3 to These and other objects of the invention will become 3.0. - apparent from the description of the invention given Any soluble form of rhodium is acceptable for the herein below. preparation of invention catalyst, including any insolu BRIEF DESCRIPTION OF THE INVENTION ble form which will dissolve under the conditions of the reaction. These forms include rhodium salts such as In accordance with the present invention, there is 65 rhodium nitrate, rhodium sulfate, rhodium chloride, provided a method for converting ethylene oxide into rhodium bromide, rhodium iodide, rhodium fluoride, difunctional compounds having a three-carbon chain. rhodium oxide, rhodium phosPhate, and the like; or These products include 1,3-disubstituted compounds organic rhodium salts such as rhodium formate, rho 5,135,901 3 4. dium acetate, rhodium propionate, rhodium butyrate, divided finely enough by mechanical means such as and the like; or aromatic rhodium salts such as rhodium ruthenium powder, ingot, shot, sponge, or wire. Of benzoate, rhodium phthalate, rhodium naphthenate, and course, one preferred form, by analogy to its nickel the like. More preferable forms because of their greater analog, would be Raney ruthenium. solubilities are rhodium complexes including any of the The Group Va promoter can be from any member of rhodium carbonyls, rhodium(III)tris(2,4-pentanedion the series of elements including nitrogen, phosphorous, ate), rhodium(I)dicarbonyl(2,4-pentanedionate), dir arsenic, or antimony. Preferably, the promoter used is hodium tetracarbonyl dichloride, iodo rhodium(I)tris(- present in their most reduced forms as tertiary organic triphenylphosphine), bromo rhodium(I)tris(triphenyl derivatives. phosphine), chloro rhodium(I)tris(triphenylphosphine), 10 Examples of suitable Group Va bond promoter cata fluoro rhodium(I)tris(triphenylphosphine), rhodium(I)- lysts include tertiary alkyl amines such as triethyl carbonyl chlorobis(triphenylphosphine), rhodium(I)hy amine, tripropyl amine, tributyl amine, etc.; cyclicter drido carbonyl tris(triphenylphosphine), or other solu tiary amines such as N-methylpiperidine, N-methylpyr ble rhodium complexes within the spirit of this group. rolidine, and 1,4-diazabicyclo2,2,2Octane; tertiary aro The concentrations of rhodium under which the in 15 matic amines such as triphenyl amine, trinaphthyl vention reactions will take place are 106 molar to 10 anine, etc.; mixed alkyl, aromatic, and alkyl-aromatic molar more preferably 10 to 3 molar; and most pref amines from the previous examples; and, pyridines. erably 102 molar to 1 molar. Suitable phosphines include tertiary alkyl phosphines The ruthenium component, which is optional for the such as trimethyl phosphine, triethyl phosphine, tri production of 3-hydroxyester products, but which is 20 propylphosphine, tributyl phosphine, trioctylphos more important in the production of 6-hydroxypro phine, tricyclohexylphosphine, tribenzyphosphine, etc.; pionaldehyde, should be present in concentrations de tertiary aromatic phosphines such as triphenylphos pendent upon that of the primary rhodium component. phine, tris(p-tolyl)-phosphine, tris (p-methoxyphenyl)- It should be at least 0.001 to 1000 times the concentra phosphine, tris(a-naphthyl)phosphine, etc.; and, mixed tion of rhodium. More preferably, the concentration 25 alkyl, aryl, or alkyl-aryl tertiary phosphines. should be 0.02 to 50 times the rhodium concentration. Suitable arsines include tertiary arsines such as triphe The most preferred ruthenium concentrations are 0.5 to nylarsine and suitable stibines include triphenylstibene. 10 times the rhodium concentration. The higher ruthe The optimum concentration of these promotors de nium concentrations should be present if reduced or pends on the concentration of the primary catalyst ganic products are desired. 30 metal, rhodium. It should preferably be at least 0.1 to The form of the ruthenium is not as critical as that of 100 times the molar concentration of the rhodium com the rhodium. Thus, it may be present in the form of a ponent; more preferably from 0.5 to 20 times the con soluble homogeneous component or as a finely divided centration; and most preferably from 1 to 10 times the metal both of which are capable of catalyzing the re molar concentration of rhodium. The reaction will take duction of organic functional groups although the dif 35 place outside of these constraints but at unacceptable ferent forms have different susceptibilities to inhibition rates due to either too little promoting effect for the by the Group Va promoters. very low concentrations or too great an inhibiting effect The soluble ruthenium components may be added in for the very high concentrations, especially during later any of a number of forms including inorganic salts such hydrogenation reactions on heterogeneous ruthenium. as ruthenium nitrate, ruthenium sulfate, ruthenium fluo For this same reason and the fact that the reactions run ride, ruthenium chloride, ruthenium bromide, ruthe under more forcing conditions, the hydrogenated prod nium iodide, ruthenium oxide, and ruthenium phosphate uct, B-hydroxy propionaldehyde is prepared using the or organic ruthenium salts such as ruthenium formate, smaller amounts of the Group Va promoters within the ruthenium acetate, ruthenium propionate, ruthenium preferred limits. butyrate, etc., or aromatic ruthenium salts such as ruthe 45 nium benzoate, ruthenium phthalate, ruthenium naph Production of (3-Hydroxyester Products thenate, etc. For the preparation of 3-hydroxypropionate ester Ruthenium complexes are often more soluble than products, synthesis gas, ethylene oxide, a primary C1-6 the salts and are, therefore, more desirable if high con alkyl alcohol or benzyl alcohol, and the catalyst pro centrations of homogeneous ruthenium solutions are 50 vided by the present invention are contacted at a tem desired. These complexes include ruthenium(III)- perature from 40° C. to 120° C. The synthesis gas used tris(2,4-pentanedionate), ruthenium(II)dichloro tris(tri will preferably have a hydrogen to carbon monoxide phenylphosphines), ruthenium(II)dichloro tetrakis-(tri molar ratio from 0 to 0.5. phenylphosphine), ruthenium(II)hydrido chloro tris(tri To optimize the yield of g-hydroxyester, the catalyst phenylphosphine), or other soluble ruthenium com 55 need be made of only soluble rhodium promoted with a plexes within the spirit of this group. Group Va promoter such as a tertiary amine. The pres The insoluble or heterogeneous ruthenium forms may ence of excess ruthenium is in no way detrimental to this be introduced as any of the forms given above which reaction and in fact contributes marginally to the suc under a sufficiently hydrogen rich atmosphere or reduc cess of the reaction, although the reaction will take ing environment prior to the introduction of the soluble place entirely in its absence with no decrease in selectiv rhodium will give finely divided ruthenium. This ity. The inertness of ruthenium toward detrimental side method is the preferred one for giving the most highly reactions is very important and leads to the success of divided ruthenium. the later reactions. It may, however, be produced by reducing a soluble The primary C1-6 alkyl alcohol used in accordance ruthenium form in the presence of a suitable support to 65 with this embodiment of the present invention is em give finely divided ruthenium deposited on supports ployed in an amount which is at least equimolar with including activated charcoal, alumina, silica gel, or the amount of oxirane used, but preferably higher zeolites. Other forms may be included if they can be amounts are used. For example, molar amounts of 1 to 5,135,901 5 6 10 times of oxirane may be used. The alcohol may also The preferred synthesis gas ratios employed in accor serve as the reaction solvent. The primary C1-6 alkyl dance with this embodiment of the present invention are alcohol used can include methyl alcohol, ethyl alco a hydrogen to carbon moroxide ratio of 0.3 to 3. More hol, n-propyl alcohol, n-butyl alcohol, n-pentyl alcohol, preferred ratios are 0.5 to 2; with the most preferred n-hexyl alcohol, 2-methyl-1-propanol, 2-methyl-1- ratio being 0.7 to 1.5. butanol, 3-methyl-1-butanol, 2-methyl-1-pentanol, 3 The pressure under which this synthesis gas is utilized methyl-1-pentanol, or 4-methyl-1-pentanol. The alcohol is the same as for the preparation of 6-hydroxy propio used may also be benzyl alcohol. nate esters, which is 500 to 10,000 psig. A more pre The reactions may be conducted with no additional ferred pressure is 1,000 to 5,000 psig, and the most pre solvent for the As-hydroxy propionate ester prepara O ferred pressure range is 2,000 to 4,000 psig. Under these tions. However, the preferred solvent is the alcohol most preferred conditions and catalyst concentration, portion of the ester. In this latter case, as noted above, the reaction is usually complete within 0.5 to 2 hours. at least one molar equivalent of the alcohol is required It is desirable, in order to optimize formation of g but up to a several fold excess of the alcohol may be hydroxy propionaldehyde, that ethylene oxide conver used as solvent with no detrimental effect, 15 sions are maintained below about 30%. While reaction Of course, in all of these preparations, additional inert continues at conversions above 30% at such higher solvents may be utilized. Frequently, highly desirable conversions, the selectivity to the desired product falls effects are obtained in that the components of the reac off as a result of further reaction with by-product water tion upon completion are extracted into different phases (formed by dehydration of the hydroxy-aldehyde inter to keep the side reactions to a minimum. Included as 20 mediate). In addition, by-product water can also react suitable solvents are aliphatic hydrocarbons such as with ethylene oxide to produce other by-product mate pentane, hexane, heptane, octane, and the like; aromatic rials. hydrocarbons such as benzene, toluene, xylene, ethyl This invention provides a new method for making a benzene, and the like; esters such as dimethyl ether, range of carbonylation and/or hydrogenative carbony diethyl ether, dipropyl ether, dibutyl ether, tetrahy 25 lation difunctional products from ethylene oxide using a droduran, tetrahydropyan, and the like; halogenated novel ruthenium/rhodium catalyst. While the usual solvents such as chloroform, carbon tetrachloride, tet catalyst for this type reaction is based on cobalt, it has rachloroethane, and the like; polar aquatic solvents such surprisingly been discovered that rhodium is about ten as sulfonane, and the like; as well as mixtures of any two times more active than cobalt for the carbonylation and or more thereof. 30 hydroformylation reactions, and that ruthenium is The conditions under which these reactions are con about five times more active for the hydrogenation. The ducted are very important and will in large part deter combined ruthenium/rhodium catalyst is, therefore, up mine the product isolated. In order to prepare f3 to fifteen times more active for converting ethylene hydroxy propionate esters, ethylene oxide and the re oxide into desirable difunctional products. quired alcohol are reacted at temperatures preferably 35 The mode of action of cobalt during its catalysis of from 40° C. to 120' C. A more preferable temperature is synthesis gas condensation with ethylene oxide would 50 C. to 100' C. and the most preferable temperature is lead to the conclusion that rhodium or ruthenium based 60 C, and 80 C. catalyst would be far less effective. Indeed the activity Since this reaction is a pure carbonylation reaction, of rhodium or ruthenium catalysts is less than one-third the synthesis gas used should be especially rich in car that of cobalt catalysts in the absence of the Group Va bon monoxide. The preferred synthesis gas composition promoter. Introduction of this promoter causes the has a hydrogen to carbon monoxide ratio ranging from course of the reaction to change entirely so that the 0 to 0.5. A more preferred range is 0 to 0.3 and the most combination of rhodium/ruthenium is much more ac preferred range is 0. to 0.1. Although this reaction is a tive. The combination of rhodium and ruthenium in this pure carbonylation, a small amount of hydrogen ap 45 catalyst extends its versatility so that a variety of prod pears to have an activating effect on the catalyst. ucts are accessible. The synthesis gas should be used at pressures ranging Other features of the invention will become apparent from 500 to 10,000 psig. A more preferred range is 1,000 in the course of the following description of exemplary to 5,000 psig, and the most preferred range is 2,000 to embodiments which are given for illustration of the 4,000 psig. Within the most preferred conditions and 50 invention and are not intended to be limiting thereof. catalyst concentrations, these reactions are usually com EXAMPLE 1 METHYL plete within 2 to 4 hours. p-HYDROXYPROPIONATE Preparation of B-Hydroxypropionaldehyde To a nitrogen flushed 300 mL Hastelloy Cautoclave To prepare 3-hydroxypropionaldehyde, or more 55 was charged 2.5 mmole of rhodium(I)hydrido carbonyl properly its dimer, 203-hydroxyethyl) 4-hydroxy-1,3- tris(triphenylphosphine), 10 mmole of ruthenium(III)- dioxane, the conditions need be only slightly more forc tris(2,4-pentanedionate), 37.5 mmole of triethylamine, ing than employed for preparation of 6-hydroxy propi 50 mL of anhydrous methanol, and 50 mL of ethylene onaldehyde, but the synthesis gas should be much richer oxide. The head was torqued on and the contents were in hydrogen. With or without a suitable solvent, other stirred rapidly while the autoclave was charged to 2,000 than an alcohol, the reaction takes place in a tempera psig with carbon monoxide. The solution was then ture range of 50° C. to 130' C. A more preferred range heated to 70' C. During this time, the pressure increased is 60' C. to 120° C. and the most preferred range is 70' to 2,200 psig and was maintained at that level by peri C. to 100 C. odic recharging from an external reservoir. The reac As is the case with the preparation of the g-hydroxy 65 tion was conducted for a total of 4 hours during which propionate ester, the catalyst need not contain the ru time the total pressure drop mounted to 1,050 psig, thenium component but must contain the rhodium and Analysis of the product upon completion of the reaction the promoter components. revealed a ethylene oxide conversion of 90.3 percent 5,135,901 7 8 with selectivity to methyl g-hydroxypropionate of 66.0 percent, g-methoxypropionate of 3.0 percent, 6 EXAMPLE 5 B hydroxypropionic acid of 2.4 percent, methyl (3- HYDROXYPROPIONALDEHYDE hydroxyethoxy)propionate of 12.3 percent, and 11.0 To a nitrogen flushed 300 mL Hastelloy Cautoclave percent miscellaneous. 5 was charged 2.5 mmole hydrido carbonyl rhodium(I)- tris(triphenylphosphine), 10 mmole ruthenium(III)- EXAMPLE 2 METHYL tris(2,4-pentanedionate), 15 mmole triethylamine, and B-HYDROXYPROPIONATE 100 mL ethylene oxide. The head was torqued on and To a nitrogen flushed 300 mL Hastelloy B autoclave the contents were stirred and the autoclave was was charged 2.5 mmole of rhodium(II)bis(2-ethylhex 10 charged with 2,000 psig of synthesis gas (H2/CO= 1/1). anoate), 10 mmole of ruthenium(III)tri(2.4 pentanedion The contents were heated to 80° C. at which point the ate), 5 mmole of a,a'-bipyridyl, 50 mL anhydrous meth pressure had climbed to 2,200 psig. The pressure was anol, and 50 mL ethylene oxide. The head was torqued maintained at this level throughout the reaction by on and the contents were stirred and charged to 2,000 periodic recharging from an external reservoir. The psig with carbon monoxide. The temperature was raised 15 reaction was conducted for 4 hours during which time to 70° C. at which point the pressure had climbed to the pressure drop amounted to 650 psig. Analysis of the 2,200 psig. It was maintained at this level by periodic product upon completion of the reaction revealed an recharging from an external reservoir. The reaction was ethylene oxide conversion of 29.4 percent with the conducted for 4 hours during which time the pressure selectivity to £8-hydroxypropionaldehyde dimer of 89.7 dropped by 150 psig, Analysis of the product mixture 20 percent, to ethanol of 5.6 percent, to propionaldehyde revealed a conversion of 26.3 percent with the selectiv of 2.5 percent, and 2.2 percent miscellaneous. EXAM ity to methyl (3-hydroxypropionate of 43.5 percent, to PLE 6 B- HYDROXYPROPIONALDEHYDE (3-methoxyethanol of 6.4 percent, to methyl 6-methoxy To a nitrogen flushed 300 mL Hastelloy Bautoclave propionate of 4.4 percent, to 6-hydroxypropionic acid was charged 2.5 mmole hydrido carbonyl rhodium(I)- of 4.6 percent, to methyl g-(2-hydroxyethoxy)propion 25 tris(triphenylphosphine), 10 mmole ruthenium(III)- ate of 22.1 percent, and 19.0 percent miscellaneous. tris(2,4-pentanedionate), 12.5 mmole a,a'-bipyridyl, and 100 mL ethylene oxide. The head was torqued on and EXAMPLE 3 METHYL the contents were stirred and the autoclave was B-HYDROXYPROPIONATE charged with 2,000 psig of synthesis gas (H2/CO= 1/1). To a nitrogen flushed 300 mL Hastelloy C autoclave 30 The contents were heated to 80° C. at which point the was charged 2.5 mmole of hydrido carbonyl rhodium pressure had climbed to 2,200 psig. At this point, the (I)tris(triphenylphosphine), 10 mmoles of ruthenium synthesis gas pressure was raised to 3,000 psig and main (III)tris(2,4-pentanedionate), 10 mmole triphenylphos tained at this level periodic recharging from an external phine, 50 mL absolute methanol, and 50 mL ethylene reservoir. The reaction was conducted for 6 hours dur oxide. The head was torqued on and the contents were 35 ing which time the pressure drop amounted to 725 psig. stirred and charged with 2,000 psig of carbon monox Analysis of the product mixture revealed an ethylene ide. The autoclave was heated to 70° C at which point oxide conversion of 27.3 percent with the selectivity to the pressure rose to 2,200 psig at which level it was R-hydroxypropionaldehyde dimer of 67.0 percent, to maintained by periodic recharging from an external ethanol of 10.9 percent, to propionaldehyde of 11.6 reservoir. The reaction was conducted 4 hours during percent, to ethylene glycol of 4.2 percent, to 1-propanol which time the pressure drop amounted to 400 psig. of 1.5 percent, and 4.8 percent miscellaneous. Analysis of the product mixture revealed a conversion Obviously, numerous modifications and variations of of 31.2 percent with the selectivity to methyl g-hydrox the present invention are possible in light of the above ypropionate of 17.4 percent g-methoxyethanol of 31.9 teachings. It is therefore to be understood that within percent, methyl g-methoxypropionate of 18.4 percent, 45 the scope of the appended claims, the invention may be phydroxypropionic acid of 6.4 percent methyl (3- practiced otherwise than as specifically described hydroxyethoxy)propionate of 4.0 percent, methyl acry herein. late 9.7 percent, and 12.2 percent miscellaneous. We claim: 1. A catalyst composition comprising: EXAMPLE4 B-HYDROXYPROPIONALDEHYDE 50 (i) a rhodium component, To a nitrogen flushed 300 mL Hastelloy C autoclave (ii) a ruthenium component 0.001 to 1000 times the was charged 2.5 mmole of hydrido carbonyl rhodium molar concentration of said rhodium component, (I)tris(triphenylphosphine), 10 mmole of ruthenium and (III)tris(2,4-pentanedionate), 17.5 mmole triphenyl (iii) a promoter component 0.1 to 100 times the molar phosphine, and 100 mL ethylene oxide. The head was 55 concentration of said rhodium component; torqued on and the contents were stirred and the auto wherein said rhodium component is a rhodium salt or a clave charged with 2,000 psig of synthesis gas rhodium complex, (H2/CO= 1/1). The contents were heated to 80 C. at wherein said rhodium component is soluble homogene which point the pressure had climbed to 2,200 psig. The ous ruthenium compound or a finely divided ruthe pressure was maintained at this level throughout the nium metal, and reaction by periodic recharging from an external reser wherein said promoter component is a nitrogen-con voir. The reaction was conducted for 6 hours during taining compound, a phosphorus-containing com which the pressure drop amounted to 950 psig, Analysis pound, an arsenic-containing compound, or an an of the product upon completion of the reaction revealed timony-containing compound. an ethylene oxide conversion of 28.5 percent with the 65 2. The catalyst composition of claim 1 wherein said selectivity to g-hydroxypropionaldehyde of 74.5 per rhodium component is at least one member selected cent, to ethanol of 203 percent, to propionaldehyde of from the group consisting of rhodium nitrate, rhodium 2.2 percent, and 3.0 percent miscellaneous. sulfate, rhodium chloride, rhodium bromide, rhodium 5,135,901 10 iodide, rhodium fluoride, rhodium oxide, rhodium phos ruthenium benzoate, ruthenium phthalate, ruthenium phate, rhodium formate, rhodium acetate, rhodium pro naphthenate, ruthenium(III)tris(2,4-pentanedionate), pionate, rhodium butyrate, rhodium benzoate, rhodium phthalate, rhodium naphthenate, rhodium carbonyls, ruthenium(II)dichloro tris(triphenylphosphine), ru rhodium(III)tris(2,4-pentanedionate), rhodium(I)dicar thenium(II)dichloro tetrakis(triphenylphosphine), and bonyl(2,4-pentanedionate), dirhodium tetracarbonyl ruthenium(II)hydrido chloro tris(triphenylphosphine). dichloride, iodo rhodium(I)tris(triphenylphosphine), 4. The catalyst composition of claim 1 wherein said bromo rhodium(I)tris(triphenylphosphine), chloro promoter component is at least one member selected rhodium(I)tris(triphenylphosphine), fluoro rhodium(I)- from the group consisting of triethyl amine, tripropyl tris(triphenylphosphine), rhodium(I)carbonyl chloro O amine, tributyl amine, N-methyl piperidine, N-methyl bis(triphenylphosphine), and rhodium(I)hydridocarbo pyrrolidine, 1,4-diazabicyclo2,2,2)octane, triphenyl nyl tris(triphenylphosphine). amine, trinaphthyl amine, pyridines, trimethyl phos 3. The catalyst composition of claim 1 wherein said phine, triethyl phosphine, tripropylphosphine, tributyl ruthenium component is at least one member selected phosphine, trioctylphosphine, tricyclohexylphosphine, from the group consisting of ruthenium nitrate, ruthe 15 tribenzyphosphine, triphenylphosphine, tris(p-tolyl)- nium sulfate, ruthenium fluoride, ruthenium chloride, phosphine, tris (p-methoxyphenyl)phosphine, tris (a- ruthenium bromide, ruthenium iodide, ruthenium oxide, naphthyl)phosphine, triphenylarsine, and triphenylsti ruthenium phosphate, ruthenium formate, ruthenium bine. acetate, ruthenium propionate, ruthenium butyrate, k k k k Sk 20

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