CATALYSIS OF CONDENSATION REACTIONS OF AMINES

Abstract: Certain hydrogen phosphate and pyrophosphate com­ positions are employed as catalysts for organic condensa­ tion reactions. Particularly high conversions and selectivities are obtained by the use of synergistic mixtures of in cyclization reactions such as in the conversion of hydroxy­ ethylpiperazine to triethylenediamine and morpholine to dimethylaminoethylmorpholine.

Description: CATALYSIS OF CONDENSATION REACTIONS TECHNICAL FIELD OF THE INVENTION The present invention relates to organic condensation reactions effected in the presence of novel pyrophosphate and hydrogen phosphate catalysts and is more particularly concerned with the production of amine compounds in enhanced yields. BACKGROUND OF THE PRIOR ART Organic synthesis by condensation reactions resulting in the loss of a molecule of water or of ammonia are well known in the art. Certain of such reactions are generally effected in the presence of acidic catalysts. An important area in which such acid catalysis has been employed is in cyclization reactions as in the synthesis of triethylenediamine and its C-substituted homologues. The catalysts more generally used or proposed for use in such cyclization reactions are solid products of the Lewis acid type. Triethylenediamine, also called diazabicyclo -[2.2.2]- octane, has been widely employed commercially as a catalyst in organic isocyanate reactions with compounds containing labile hydrogen, as in the production of urethane polymers. Triethylenediamine (sometimes hereinafter referred to as TEDA) was initially prepared in significant quantities by methods such as that described in U.S. Patent No. 2,937,176, by passing aliphatic amines in vapor phase over acidic cracking catalyst, such as silica-alumina dried gel or acidactivated clays. Numerous other feed stocks as well as other catalysts are disclosed in subsequent patents for preparation of TEDA as well as C-alkyl derivatives thereof. Typical among these are U.S. Patents 2,985,658 and 3,166,558 employing preferably silica-alumina type catalyst, but listing also other useful solid acid catalysts that can be employed such as alumina in which phosphate or fluoride ion is incorporated (U.S. 2,985,658). Among other catalysts proposed in the patent art for preparation of triethylene di amine and/or C-alkyl homologues thereof, are certain phosphate compounds, particularly aluminum phosphate. The use of aluminum phosphate as a catalyst in the preparation of heterocyclic compounds from aliphatic amines was early disclosed in U.S. Patent 2,467,205, particularly for the preparation of piperazine from ethylenediamine or from polyethylene polyamine. The use of aluminum phosphate as catalyst in the preparation of triethylenediamine accompanied by piperazine among other by-products is further described in U.S. Patent 3,172,891; while U.S. Patent 3,342,820 describes the use of complex phosphates of alkali metal and trivalent metals in the preparation of C-alkyl TEDA. U.S. Patent 3,297,701 discloses as catalysts for preparation of TEDA and C-alkyl TEDA, in addition to the preferred aluminum phosphate stated to be superior, other phosphate compounds including calcium and iron phosphates among other listed metal phosphates. In the conversion of N-aminoethylpiperazine to triethylenediamine over aluminum phosphate catalyst, at most up to 39 mol% triethylenediamine is said to be obtained. Other of the named metal phosphate catalysts in the examples of the patent obtain yields of less than 10 mol% TEDA. Acid metal phosphate catalysts, particularly phosphates of boron, aluminum and trivalent iron, have also been proposed for use in intramolecular cyclic dehydration reactions and other condensation reactions involving amino compounds. Examples of such reactions are found in U.S. Patent 4,117,227, which discloses conversion of an N-substituted diethanolamine to the corresponding N-substituted morpholine. U.S. Patent 4,036,881 describes preparation of non-cyclic polyalkylene polyamines by condensation of an alkylene diamine with an ethanolamine. N-hydroxethylmorpholine is condensed with morpholine in the presence of aluminum phosphate catalyst to form dimorpholino ethane according to U.S. Patent 4,103,087. Similarly, dimorpholinodiethyl ether is obtained by condensation of hydroxyethyl morpholine with aminoethyl morpholine over iron, aluminum or boron phosphate in U.S. Patent 4,095,022. Reaction of piperazine with ethanolamine over such acidic metal phosphate produces N-aminoethyl piperazine according to U.S. Patent 4,049,657. U.K. Patent 1,492,359 discloses the preparation of morpholine compounds by reacting an aminoalkoxyalkanol compound over phosphoric acid and similar types of phosphorus-containing substances. Pyrophosphates of lithium, sodium, strontium and barium have been used as dehydration catalysts; see U.S. Patent 3,957,900. Phosphates and pyrophosphates of strontium and nickel have been used for the dehydrogenation of, for example, n-butene to butadiene under the conditions described in U.S. Patent 3,541,172. SUMMARY OF THE INVENTION It has now been found that high yields of organic compounds are selectively obtained when the condensation reaction thereof is carried out in the presence of catalytic amounts of a catalyst selected from the group consisting of the pyrophosphate, monohydrogen phosphate and dihydrogen phosphates of strontium, copper, magnesium, calcium, barium, zinc, aluminum, lant.,anum, cobalt, nickel, cerium, neodymium, and mixtures thereof. DETAILED DESCRIPTION OF THE INVENTION The monohydrogen and dihydrogen phosphate catalysts of the present invention are prepared by reaction of a mono- or diphosphate of an alkali metal or ammonium with a soluble salt of strontium, copper, magnesium, calcium, barium, zinc, aluminum, lanthanum, cobalt, nickel, cerium or neodymium at ambient temperatures. The highest purity and best yields of the present invention are obtained when using the soluble metal salts of a strong acid such as the metal nitrates, in substantially stoichiometric proportion to the phosphate. In aqueous media under these conditions, the reaction mixture is at a pH of about 3.5 to 6.5. In general, to obtain a precipitate of desired high content of the metal monohydrogen or dihydrogen phosphate, the ratio of phosphate to metal salt in the reaction mixture should be such as to have a pH of 5 + 3, or the mixture should be adjusted to that pH range The pyrophosphate form of the catalysts of the present invention are prepared by heat treating the metal monohydrogen or dihydrogen phosphate product at temperatures above about 3000C up to 7500C in the presence of a mixture of steam and air, preferably at least about 20% by volume of steam. For use as a catalyst, the metal pyro-, monohydrogen or dihydrogen phosphate product may be employed in the form of irregular particles of the desired size range prepared by breaking up the washed and dried filter cake or in the form of regular shaped pellets obtained by known methods of casting or extruding or the product may be deposited or otherwise impregnated into the pores of a microporous substrate such as alumina, silica, silica-alumina, and the like. In using the catalyst of the present invention to catalyze organic condensation reactions, substantially the same conditions may be employed as when using the known catalysts for the particular synthesis. For optimum results, however, some adjustment in temperature, diluent and/or space rate may be found beneficial. Some specific examples of the type of organic compounds selectively obtained by the method of this invention include TEDA, the aliphatic alkylamines such as methylamine, methylethylamine, dimethylethylamine, morpholine, and dimethylaminoethylmorpholine. In the production of these compounds, the temperature is in the range of about 2850 to 4200C, the pressure is in the range of about 0.1 to 1.5 atmospheres, and the liquid hourly space velocity (LHSV) of the organic feed stock per volume of catalyst is in the range of about 0.05 to 1.5. Preferably depending on the particular reaction, the temperature is in the range of about 300 to 4000C, the pressure is in the range of about 0.3 to 1.0 atmospheres and the LHSV is in the range of about 0.1 to 0.3 to obtain the highest yields and most economical process. The operable ratio of the organic feeds to water diluent is about 10 to 90% on a weight basis and preferably, 20 to 80% by weight. The optimum yield of these compounds is likely to be obtained using the highest temperature in the preferred range at the lowest LHSV. In the preparation of TEDA, the preferred catalyst is selected from the group consisting of monohydrogen phosphate of calcium, magnesium, zinc, mixtures of strontium and barium in the ratio of Sr to Ba of about 1 to 5 to 5 to 1 and mixtures of lanthanum and strontium in the ratio of La to Sr of about 15 to 1 to 15. The organic feed stock used in this reaction to produce TEDA is a substituted piperazine compound selected from the group consisting of hydroxyethylpiperazine and aminoethylpiperazine. The¯catalysts of this invention are relatively uneffected by the purl. of the feed stock. For example, high conversion and good yields can be obtained from crude hydroxyethylpiperazine which contains minor quantities of piperazine and bis hydroxyethylpiperazine. In the preparation of dimethylaminoethylmorpholine (DMAEM), the preferred catalyst is a mixture of strontium and nickel monohydrogen phosphate in the ratio of Sr to Ni of about 1 to 5 to 5 to 1. The feed stock is morpholine and dimethylethanolamine in the molar ratio in the range of about 1 to 3 and 3 to 1. Preferably, the reaction takes place in the presence of hydrogen in the molar ratio of hydrogen to organic feed of about 1 to 1 to 20 to 1 and an inert gas such as nitrogen, argon or helium in the molar ratio of inert gas to organic feed of about 1 to 1 to 20 to 1. In the preparation of morpholine compounds, e.g. morpholine and alkyl morpholine, wherein the alkyl group has from 1 to 6 carbon atoms, diglycolamine compounds, e.g. diglycolamine and alkyl diglycolamines, wherein the alkyl group has from 1 to 6 carbon atoms are preferably carried out in the presence of strontium monohydrogen phosphate at about 300 to 3700C with the other conditions remaining the same as that discussed above. This reaction also preferably takes place in the presence of the inert gas in ratios of 2 to 1 to 10 to 1 inert gas to liquid organic feed stock. The methods and catalysts of this invention are also capable of reacting an alcohol and a nitrogencontaining compound selected from the group consisting of ammonia, aliphatic primary and secondary amines, and aromatic primary and secondary amines to selectively convert this compound to the corresponding symmetrical or unsymmetrical higher molecular weight amine with little, if any, conversion to the corresponding by-products of thermodynamic amine equilibration. The amines and alcohol in the feed stock each contain 1 to 20 carbons per molecule. Preferably, the catalyst is lanthanum or copper monohydrogen phosphate and the molar ratio of alcohol to nitrogen-containing compound ranges from about 1 to 6 to 6 to 1. CATALYST PREPARATION Example 1 200 grams of strontium nitrate [Sr(N03)2] was dissolved in distilled water and brought to a total volume of 800 cc with distilled water. To this solution there was added 10 cc of 85% phosphoric acid followed by 34.5 cc of 50% sodium hydroxide added rapidly with vigorous stirring. The resultant fine white precipitate was stirred for 10 minutes, vacuum-filtered and waterwashed. The obtained filter cake was air dried in a static oven at approximately 1100C and extruded into 1/8 inch pellets for evaluation. The obtained product had a surface area of 10-15 m2/g. By X-ray diffraction the principal component was identified as ss -SrHP04 with minor quantities of Sr5(0H) (P04)3 and unreacted Sr(NO3)2. Infrared spectroscopy showed a spectrum consistent with SrHPO4. (Ref: Richard A. Nygurst and Ronald O. Kagel, "Infrared spectra of Inorganic Compounds", page 163, 1971). Example 2 195 grams of barium nitrate --Ba(NO3)2-- and 53 grams of strontium nitrate --Sr(N03)2-- were dissolved in distilled water and diluted to 500 cc. 132 grams of dibasic ammonium phosphate --(NH4)2HPO4-- were dissolved in distilled water and diluted to 500 cc with heat. The three salt solutions were then combined with heat and stirred for about 10 minutes. The combined solution was vacuum filtered and the resulting precipitate was washed with distilled water and air dried overnight in a static oven at approximately 1100C. The filter cake was broken up into small (1/8 to 1/4 inch) irregular granules for evaluation. The resulting product had a surface pH of 4-5 as determined by acid base indicators and the ratio of strontium to barium in the product was found to be 1 to 3.5. Example 3 The procedure for preparing the Example 2 was carried out except that 130 grams of Ba(N03)2 and 106 grams of Sr(N03)2 were dissolved in distilled water in place of the 195 and 53 grams respectively. The product had a surface pH of 4-5 and a Sr/Ba ratio of 2/1 mol/mol. The resulting catalyst was in the form of a fine powder and was deposited on an inert, low surface area Alundum silica-alumina core using a powder-coating step. The step comprised placing the amount of catalyst to be coated into a jar with the Alundum spheres and rotating on a jar-mill for several days to cause the catalyst powder to adhere to the spheres. The resulting coated spheres contained 25% of the active catalyst and 75% inert. Example 4 212 grams of Sr(N03)2 were dissolved in distilled water and diluted to 500 cc. 115 grams of ammonium dihydrogen phosphate --NH4H2PO4-- were dissolved in distilled water and diluted to 500 cc. The remaining steps of the catalyst procedure of Example 2 were carried out. The resulting catalyst was believed to contain less than 5% strontium dihydrogen phosphate --Sr(H2P04)2-- with the balance being SrHPO4. The surface pH of this catalyst mixture was 4-4.6 in comparison to substantially pure strontium monohydrogen phosphate which has a surface pH of 4.8-5.4. Substantially pure strontium dihydrogen phosphate was found to have a surface pH of 0.2-1.2; see Example 21. The product of this example was deposited on the silica-alumina spheres in the same manner as set forth under Example 3. Example 5 The same procedure for preparing the catalyst of Example 1 was carried out except that 236 grams of calcium nitrate --Ca(N03)2.4H2O-- and 115 grams of NH4H2PO4 were combined. The resulting dried catalyst particles were coated on the silica-alumina spheres in the same manner as that of Example 3. The analysis of the catalyst formed by this procedure indicated that it consisted essentially of calcium monodihydrogen phosphate with a Ca/P ratio of 1.009 and a surface pH of 4-6. In contrast, substantially pure calcium monohydrogen phosphate had a surface pH of 5-5.5; see Example 16 below. The presence of a very small amount of calcium dihydrogen phosphate may account for the difference in the surface pH value of this catalyst. Example 6 The catalyst preparation procedure of Example 2 was repeated except that 212 grams of Sr(N03)2 were dissolved in place of the mixed barium and strontium nitrate salts and the resulting strontium monohydrogen phosphate catalyst had a surface pH of 4.8-5.2. Examples 7-15 The following salts were combined and catalysts were prepared in the manner set forth under Example 2: Catalyst Surface Example Salt Solutions Formulation pH (a) (b) 7 168g. Nd(NO3)3.5H2O 80g. (NH4)2HPO4 Nd2(HPO4)3 8 217g. Ce(NO3)3.6H2O 99g. (NH4)2HP 4 Ce2(HPO4)3 0.2-1.2 9 415g. La(NO3)3.5H2O 198g. (NH4)2HPO4 La2(HPO4)3 0.2-1.8 10 202g. Sr(N03)2+ 132g. (NH4)2HPO4 SrHP04/LaHPO 4-5 20 grams of (Sr/La=14.9/I) La(N03)3 5H20 11 291g.Co(NO3)2.6H2O 132g. (NH4)2HPO4 CoHPO4 4.6-4.8 12 291g.Ni(NO3)2.6H2O 132g. (NH4)2HPO4 NiHPO4 6.2-6.8 13 242g.CuCl2.2.5H2O 132g. (NH4)2HPO4 CuHPO4 * 14 297g.Zn(NO3)2.6H2O 132g. (NH4)2HPO4 ZnHPO4 6.2-6.5 15 125g.Al(NO3)3.9H2O 66g. (NH4)2HPO4 Al2(HPO4)3 2 *Colored product, pH N.A. Example 16 160 grams of Ca(N03)4 were dissolved in distilled water and diluted to 800 cc. 20 cc. of phosphoric acid (88% by wt. in water) were added with agitation. 34.5 cc. of sodium hydroxide solution (50% by wt. NaOH in water) were added to precipitate the CaHP04 which was filtered, washed, dried and granulated as in Example 2. The resulting product had a surface pH of 5-5.5. Controls 1-3 The following salts were also combined in the manner of the Example 1 preparation. Catalyst Control Salt Solutions Formulation (a) (b) 1 261g.Ba(NO3)2 230g. NH4HSO4 BaSO4 2 75g. CsCl 40g. (NH4)2HPO4 CsHP04= 3 106g. Sr(N03)2 40g. 50% NaOH+ SrHAsO4 80g.(NH4)2H2AsO4 *Did not form a precipitate. Control 4 200 grams of Sr(N03)2 were dissolved in distilled water and diluted to 400 cc. 92 grams of H2SO4 were diluted in 200 cc. of distilled H20. 75 grams of 50 wt. % NaOH solution were diluted to 200 cc. with distilled water. The H2SO4 and NaOH solutions were mixed together slowly. The Sr(N03)2 solution was stirred into the solution containing 112504 and NaOH. The solution was stirred for 10 minutes and the precipitate was filtered, washed and dried. The surface pH of the resulting catalyst was less than 3 which was believed to be substantially all SrSO4. Example 17 71 grams of Na2HPO4 were dissolved in 500 cc. of distilled water. 101.7 grams of MgCl2.6H2O were dissolved in 500 cc. of distilled H20. Both solutions were mixed together and the precipitate was filtered1 washed and dried. The surface pH of the MgHPO4 product was 7-8. Example 18 71 grams of Na2HPO4 and 130.7 grams of Ba(N03)2 were each separately dissolved in 500 cc. of distilled H20. The 2 solutions were mixed and the precipitate was filtered, washed and dried. The resulting BaHPO4 had a surface pH of 8-9. Each of the products resulting from the procedures of Examples 17 and 18 above were coated on the silicaalumina spheres in the same manner as indicated in Example 3. Example 19 The SrHPO4 catalyst of Example 6 was heat treated for 2 hours in the presence of a mixture 20% by volume steam and the balance air at 3500C. The resulting strontium pyrophosphate (Sr2P207) had a crushing strength of 0.47 kg./mm of length and a packed bulk density of 1.01 kg./l. Example 20 The ZnHPO4 catalyst product of Example 14 above was coated on the silica-alumina spheres in the manner set forth in Example 3. Example 21 132.5 grams of strontium hydroxide octahydrate --Sr(OH)2.8H2O-- were dissolved in a solution of 750 cc. of 85% phosphoric acid and 1500 cc. of distilled water. The resulting solution was slowly evaporated to a total volume of about 900 cc. with the temperature being maintained at 250 to 300C The solution was cooled to 50C overnight and a white precipitate was recovered by vacuum filtration. The resulting Sr(H2PO4)2 precipitate was washed with 5-300 cc. portions of anhydrous ethanol and with 2-200 cc. portions of anhydrous ether. The product was dried at room temperature under vacuum for 6 hours. An elemental analysis of the product showed a P/Sr mol ratio of 2.04 and the surface pH was found to be 0.2-1.2. The fine powder was pressed into tablets the size of a typical aspirin tablet and crushed to granules 1/8 to 1/4 inch in size. Example 22 The fine powder of the catalyst prepared in accordance with Example 21 was deposited on silica-alumina spheres in the manner set forth in Example 3. Example 23 2000 grams of Sr(N03)2 were dissolved in 2000 cc of deionized water and the solution diluted to 4000 cc with deionized water after dissolution of the Sr(N03)2 was complete. In another container, 1342.3 grams of Na2HPO4 were dissolved in 2000 cc of deionized water. After solution of the na2HPO4 was complete, the solution was diluted to 4000 cc with deionized water. The pH of this solution was approximately 8.8. Precipitation of SrHPO4 was effected by slowly adding the Na2HP04 solution to the Sr(N03)2 solution Na2 HPO4 with rapid stirring. The white SrHPO4 precipitated rapidly from solution forming a rather thick slurry. This slurry was mixed for one hour, after which time the pH was measured to be about six. The solid SrHPO4 was recovered by filtering on an eight frame filter press using cloth filters. It was washed with deionized water. After filtering and washing, the solid was dried in a circulating hot air oven at 2500F for four hours. The yield of SrHP04 was 1680 grams. The solid was wetted and formed into pellets by extrusion through a 3.1 mm die plate and cutting the extrudates to about 1/4 inch in length. After drying the extrudate at 2500F for four hours in a circulating hot air oven, they were heat treated at 6620F for two hours in a 20% steam, 80% air atmosphere. Example 24 106 grams of Sr(N03)2 and 145 grams of Ni (NO3)2 6H20 were dissolved in distilled water and diluted to 500 cc. 132 grams of (NH4)2HPO4 were dissolved in distilled water and diluted to 500 cc. the remaining steps of Example 1 were carried out to yield a (Sr-Ni)HPO4 catalyst having a.surface pH of 5.4-7.0. USE OF CATALYSTS Examples 25-62 Each of the products prepared in accordance with Examples 1 through 22 and Controls 1 and 3-5 above were evaluated for catalytic performance for the preparation of TEDA with either a feed mixture containing hydroxyethylpiperazine (HEP) or N-aminoethylpiperazine (AEP) in accordance with the following test procedure: (a) 20 cc (approximately 6.2g.) of the catalyst was loaded into a 3/4 " 1! diameter stainless steel reactor. (b) The reactor was placed in a conventional tube furnace such that the catalyst bed was near the furnace center and therefore could be heated to a constant and uniform temperature. (c) The catalyst bed temperature was raised to a temperature of 3400-4000C over a period of 15 to 30 minutes while a small flow of gaseous nitrogen was maintained through the reactor to aid in the removal of water vapor. (d) A feed mixture containing HEP and water such that the organic component made up 60% of the mixture was then allowed to flow through the catalyst bed at a rate of 6.5-7.0 cc/hour; the nitrogen flow was discontinued. (e) The catalyst bed temperature indicated in the tables set forth below was maintained during the run and the product samples were collected and analyzed. Analyses were performed using well-established gas chromatographic techniques. The yields of TEDA and piperazine (PIP) as well as the conversion obtained from the catalysts of Examples 1-22-in Table 1 can be compared with those of Control Catalysts 1 and 3-5 in Table 2 below. TABLE 1 TEDA PRODUCTION Nominal Conver Ex- Cat. of Formu- TEDA PIP sion, ample Ex. Form lation Yield, Wt. % Yield, Wt. % Mol. % Temp., C Feed 25 1(1) Granules SrHPO4 71.5 3.7 99.3 360 HEP 26 1(1) Granules SrHPO4 80.7 3.4 99.3 360 HEP 27 1 Granules SrHPO4 71.1 7.6 95.4 370 HEP 28 2 Granules Sr/BaHPO4 83.8(2) 7.0(3) 99.9 360 HEP (Sr/Ba=1/3.5) 29 3 25% Coated Sr/BaHPO4 67.8 5.5 99.1 380 HEP Spheres (Sr/Ba=2/1) 30 3 25% Coated Sr/BaHPO4 13.8 9.1 56.8 400 AEP Spheres (Sr/Ba=2/1) 31 4 25% Coated SrHPO4/ 63.5 14.7 98.3 380 HEP Spheres Sr(H2PO4)2 32 4 25% Coated SrHPO4/ 18.8 16.4 77.0 400 AEP Spheres Sr(H2PO4)2 33 5 25% Coated CaHPO4/ 56.2 5.8 91.2 380 HEP Spheres Ca(H2PO4)2 TABLE 1 (cont'd) TEDA PRODUCTION Nominal Conver Ex- Cat. of Formu- TEDA PIP sion, ample Ex. Form lation Yield, Wt. % Yield, Wt. % Mol. % Temp., C Feed 34 5 25% Coated CaHPO4/ 34.4 9.9 90.2 380 AEP Spheres Ca(H2PO4)2 35 6 Granules SrHPO4 76.0 7.8 98.6 360 HEP 36 6 Granules SrHPO4 29.0 21.0 99.0 400 AEP 37 7 Granules Nd2(HPO4)3 18.2 5.4 98.4 340 HEP 38 7 Granules Nd2(HPO4)3 7.5 2.1 92.6 360 AEP 39 8 Granules Ce2(HPO4)3 32.3 8.4 99.9 340 HEP 40 8 Granules Ce2(HPO4)3 7.8 7.9 92.6 360 AEP 41 9 Granules La2(HPO4)3 16.2 4.2 98.8 340 HEP 42 9 Granules La2(HPO4)3 25.5 3.3 95.2 380 AEP 43 10 Granules La/SrHPO4 58.7 5.3 99.2 360 HEP (La/Sr=1/15) 43 10 Granules La/SrHPO4 58.7 5.3 99.2 360 HEP (La/Sr=1/15) 45 11 Granules CoHPO4 40.0 8.4 98.7 360 HEP 46 11 Granules CoHPO4 19.4 17.4 91.9 380 AEP 47 12 Granules NiHPO4 36.2 5.6 82.4 360 HEP TABLE 1 (cont'd) TEDA PRODUCTION Nominal Conver Ex- Cat. of Formu- TEDA PIP sion, ample Ex. Form lation Yield, Wt. % Yield, Wt. % Mol. % Temp., C Feed 48 12 Granules NiHPO4 6.0 7.8 56.7 380 AEP 49 13 Granules CuHPO4(5) 17.6 4.2 99.4 340 HEP 50 14 Granules ZnHPO4 45.9 6.7 94.7 380 HEP 51 15 Granules Al2(HPO4)3 39.7 9.4 98.3 380 HEP 52 15 Granules Al2(HPO4)3 17.1 25.8 88.4 380 AEP 53 16 Granules CaHPO4 59.2 23.5 99.6 360 HEP 54 17 25% Coated MgHPO4 47.2 15.8 99.9 380 HEP Spheres 55 18 25% Coated BaHPO4 23.2 1.0 37.4 380 HEP Spheres 56 19 Granules Sr2P2O7 30.7 9.0 98.4 340 HEP 57 19 Granules Sr2P2O7 41.0 9.0 99.2 360 HEP 58 20 25% Coated ZnHPO4 12.2 11.3 57.9 400 AEP Spheres 59 21 Granules Sr(H2PO4)2 24.7 4.4 95.5 320 HEP 60 21 Granules Sr(H2PO4)2 6.7 0.6 99.6 320 AEP 61 22 25% Coated Sr(H2PO4)2 22.0 3.6 98.9 320 HEP Spheres 62 22 25% Coated Sr(H2PO4)2 10.9 18.3 91.1 320 AEP Spheres TABLE 2 Nominal Conver Catalyst of Formu- TEDA PIP sion, Control Form lation Yield, Wt. % Yield, Wt. % Mol. % Temp., C Feed 1 Granules BaSO4 14.3 2.9 31.2 360 HEP 3 25% Coated SrHAsO4 4.6 6.2 36.2 340 HEP Speres 3 25% Coated SrHAsO4 1.2 1.6 43.5 360 AEP Spheres 4 Granules SrSO4 2.1 27.3 36.4 360 HEP 5(6) Granules AlPO4 28.4 6.0 100 wt.% 400 AEP 5(7) Granules AlPO4 33.9 26.7 83 wt.% 375 AEP (6)Data obtained from Example II of U.S. Patent 3,297,701. (7)Data obtained from Example XXI of U.S. Patent 3,297,701. The results set forth in Table where the catalysts of the examples demonstrate a, unique ability to convert over 50 mol.% of the feed to products the majority of which is TEDA. Depending on the particular feed stock, the yield of TEDA ranged from 6% in the worst case using Ni to approximately 84% in the best mode using 1 part SrHPO4 to 3.5 parts BaHP04, see Example 1 above. The former being the use of NiHPO4 with an aminoethylpiperazine feed. When the feed over NiHPO4 was changed to hydroxyethylpiperazine, the yield increased 6 fold with a corresponding increase in the conversion from approximately 57% to 82%. The BaHP04 catalysts per se did not meet the criteria for an effective catalyst for the conversion of-HEP to TEDA. However, when approximately four parts of this catalyst were combined with one part of SrHP?4 as in the Example 2, the yield of TEDA and the conversion increased based on a synergistic effect over that of the SrHP04 catalyst. Example 63 The catalyst of Example 23 was tested in the conversion of crude HEP to TEDA. The reaction was carried out at atmospheric pressure, at a liquid hourly space velocity of 0.3 and at the temperatures indicated in Table 3 below. TABLE 3 Initial After 78 Days Bed Temp., OC 360 368 HEP Conversion, wt. % 99+ 99+ TEDA Yield, wt. % 40.5 43.0 PIP Yield, wt. % 13.5 18.5 Example 64 The catalyst of Example 23 was tested for the conversion of diethanolamine to TEDA. The test was carried out at 3700C using a feed consisting of diethan olamine and water (2.0 to 1.0 mole ratio) pumped into the reactor at a rate of 4.4 liquid cc/hr along with helium diluent at a rate of 25 cc/minute. The diethanolamine was in completely converted to TEDA, as the only, i.e. about 26 mol. %, recovered product. Example 65 A 64% by weight solution of N-aminoethyl piperazine in water was passed over a catalyst composition consisting essentially of SrHPO4 at 3800C and at a liquid hourly space velocity of 0.3 volumes of liquid per volume of catalyst. In a first pass operation there was obtained 96.8 mol. % conversion of the feed compound, obtaining a yield of 34.8% by weight (40.1 mol. %) TEDA and 27.1% by weight (40.6 mol. %) PIP. Other typical condensation reactions in which SrHPO4 may be employed as a catalyst include the formation of amines by amination of the corresponding alcohols with ammonia and the formation of polyamines from glycols and diamines. It is believed that the key to the properties of the STEP04 as a highly selective catalyst is due to the presence of a specific structure, which provides a narrow range of acidity. This narrow acidity range displayed by SrHPO4 may be optimum for promoting certain types of acid catalyzed reactions, in contrast to such catalysts as alumina, silica-aluminaand the like which have acid sites of widely varying strength, and hence show relatively low selectivity for the desired reaction. Example 66 Diethyleneglycol was passed over the SrHPO4 catalyst of Example 23 in the presence of water at a temperature of 3700C and at a contact time of 6.7 seconds. The feed contained 57 vol. % diethyleneglycol and 43 vol. % 1120. The reaction product contained 33 wt. % 1,4-dioxane, corresponding to a yield of 47 mol. %. The addition of water to the organic feeds may be desirable to prevent loss of catalyst activity as a result of dehydration of the SrHPO4 to the pyrophosphate. Example 67 The SrHPO4 catalyst of Example 23 was tested for the conversion of 1, 4-butanediol to tetrahydrofuran. The test was carried out at 3500C using a feed consisting of 20 percent by volume of water and 80 percent by volume of 1, 4-butanediol pumped to the tubular reactor at a rate of 4.4 cc/hr. Helium dilutent was also fed at the rate of 30 cc/min. Under these conditions, the diol was completely converted to tetrahydrofuran. Example 68 The CAPO, catalyst of Example 5 was recovered in a fine, powdered state and was deposited on inert alumina spheres instead of the silica-alumina spheres in the same manner as set forth under Example 3. 20 cc of the resulting coated alumina contained 2 gms. of CaH?O4. The performance of this catalyst was evaluated for the preparation of an alipathic secondary amine with a feed mixture of monoethylamine (EA) and methanol using the general procedure used in Examples 25-62 for the preparation of TEDA. Specifically, 1 mol. of the primary amine and 1 mol. of the alcohol were reacted at 3500C, 1 atmosphere pressure and an LHSV of 0.15/hr. The conversion was 23.9 mol % of the ME to the secondary aliphatic amine. The yield of methylethylamine (MEA) was 16.5 mol. % of the amine feed with a selectivity of 69 mol. %. The only other product in any significant quantity was dimethylethylamine (DMEA) with a yield of 5.4 mol. % and a selectivity of 22 mol %. Example 69 The procedure of Example 68 was followed except that 1 mol. of diethylamine (DEA) was substituted for 1 mol. of EA. 27.6 mol. % of this primary amine in the feed was converted for the most part to a single secondary amine, i.e. diethylmethylamine (DEMA) and a trace amount of a tertiary amine, i.e. triethylamine. The yield of DEA fed was 23 mol. % DEMA with a selectivity of 83.3 mol. %. Examples 70-71 3 grams of the La2(HP04)3 catalyst of Example 9 were coated onto alumina spheres and the procedures of Example 60 and 69 were followed. The results from these reactions are summarized in Table 4 below. Examples 72-73 The SrHP04 catalyst of Example 6, was used to convert methanol and either monoethylamine (Example 72) or diethylamine (Example 73) in the same manner set forth under Example 68. The results of these Examples 72-73 are summarized and compared with the other Examples 68-71 in Table 4 below. TABLE 4 ALIPHATIC AMINE PRODUCTION Amine Yield, mol. % Selectivity, Mol. % Conversion Feed MEA DMEA(7) DEMA MEA DMEA DEMA Mol. % Example 68 EA 16.5 5.4 - 69 22 - 23.9 69 DEA - - 23 - - 83.3 27.6 70 EA 27 25 - 47 44 - 57 71 DEA - - 39 - - 66 59 72 EA 22 17 - 55 17 - 40 73 DEA 1.4 6.9 41 2.8 13.8 82 50 Dimethylethylamine. The data of Table 4 above illustrates the unexpectedly high selectivities to the corresponding aliphatic amine without the formation of the corresponding by-products of thermodynamic amine equilibration. The relatively low conversion to product of Examples 6 & can be attributed to the fact that only 2 gms. of CaHP04 or 3 gms. La2(HP04)3 were used in Examples. 68-71 in comparison to about 20 gms. of SrHPO4 that were used in Examples 72 and 73. Example 74 The CuHPO4 catalyst of Example 13 was coated onto alumina spheres and the procedure of Example 68 was followed except that 1 mol. of ammonia was substituted for 1 mol. of EA The results from this reaction were a 65 mol. % yield of monomethylamine (MA) based on the methanol, an 87 mol.% selectivity to MA and a methanol conversion of 75 mol. %. Example 75 The La(EP04)3 catalyst of Example 9 was deposited on alumina spheres and the procedure of Example 74 was followed. The results were yields based on the methanol in the feed of-13 mol. % trimethylamine (TMA), 2.8 mol. % dimethylamine (DMA) and 3 mol. % monomethylamine (MA), selectivities based on the methanol of 69 mol. % TMA, 14.9 mol. % DMA and 16 mol. % MA, and a methanol conversion of 52 mol. %. It has also been found that NgHPO4 and BaHPO4 were effective in selectivity converting amines to the corresponding higher molecular weight amine. Examples 76-82 The (Sr-Ni)HPO4 catalyst of Example 24 was evaluated for the preparation of N-(2-dimethylaminoethyl)morpholine (DMAEM) with a feed mixture of morpholine (MOR), dimethyl ethanolamine (DMEA), distilled water, hydrogen and helium in the amounts shown below in Table 5 using the general procedure used in Examples 25-62 for the TEDA preparation. Specifically the condensation reaction was carried out at 3400C, 1 atmosphere of pressure and an LHSV in the range of 0.31-0.44/hr. as shown in Table 5 in the presence of 20 cc. of the (Sr-Ni)HPO4 catalyst granules. Examples 83-86 The SrHPO4 catalyst of Example 6 was used in place of the (Sr-Ni)HPO4 catalyst of Example 24 and the condensation reactions were carried out in the same manner as described under Examples 76-82. The results of these runs are summarized and compared with the Examples 76-82 feed, yield and conversion data in Table 5 below. TABLE 5 DMAEM PRODUCTION Example Feed, LHSV, Yield, Mol. % Conversion, Vol. % hr. MOR Mol. % 76 MOR 60 0.31 100 16 DMEA 20 H O 20 H2e (20 cc/min) H2 (20 cc/min) 77 MOR 60 0.44 63 23 DMEA 20 H O 20 (20 cc/min) H2 (20 cc/min) 78 MOR 40 0.31 53 43 DMEA 40 H2O 20 Hue (20 cc/min) H2 (20 cc/min) TABLE 5 - (Cont'd) DMAEM PRODUCTION Example Feedr LHSV, Yield, Mol. % Conversion, Vol. % hr. MOR Mol.% 79 MOR 40 0.21 58 48 DMEA 40 H O 20 (20 cc/min) H2 (20 cc/min) 80 MOR 20 0.31 52 60 DMEA 60 H O 20 (20 cc/min) H2 (20 cc/min) 81 MOR 20 0.21 58 75 DMEA 60 H2O 20 He (20 cc/min) H2 (20 cc/min) 82 MOR 40 0.31 97 21 DMEA 20 HO 40 He (20 cc/min) H2 (20 cc/min) 83 MOR 40 0.21 42 32 DMEA 20 HO 20 He (20 cc/min) 84 MOR 40 0.21 37 28 DMEA 40 HO 20 He (20 cc/min) 85 MOR 60 0.21 43 22 DMEA 20 H2O 20 He (20 cc/min) 86 MOR 20 0.21 33 45 DMEA 60 H2O 20 He (20 cc/min) Examples 87-91 The catalyst product of Example 1 was evaluated for catalytic performance for the preparation of morpholine from diglycolamine at 1 atmosphere in accordance with the following test procedure: : (a) 10 cc (approximately 3.1 g.) of SrHPO4 was loaded into a 3/4 " diameter stainless steel reactor. (b) The reactor was placed in a conventional tube furnace such that the catalyst bed was near the furnace center and therefore could be heated to a constant and uniform temperature. (c) The catalyst bed temperature was slowly raised to a temperature of 2500C over a period of 15 to 30 minutes while a small flow of gaseous helium was maintained through the reactor in three of the examples. (d) A feed mixture containing DGA and water (except for Examples 88 and 90) in the ratio set forth in Table 6 below was then allowed to flow through the catalyst bed at an LHSV of 0.21 to 0.88; the helium flow was continued through the run (except for Examples 90-91). (e) The catalyst bed temperature indicated in Table 6 below were maintained throughout the run and the product samples were collected and analyzed. Analyses were performed using well established gas chromatographic techniques. The operating conditions and yields obtained from the catalyst of Example 1 are summarized in Table 6 below. Table 6 EMI28.1 <tb> <SEP> Example <SEP> 87 <SEP> 88 <SEP> 89 <SEP> 90 <SEP> 91 <tb> Feed, <SEP> DGA/H20, <SEP> Vol. <SEP> % <SEP> 80/20 <SEP> 100/ <SEP> 80/20 <SEP> 100/0 <SEP> 50/50 <tb> Helium <SEP> Diluent, <SEP> cc/min. <SEP> 34.5 <SEP> 34 <SEP> 28.5 <SEP> None <SEP> None <tb> Temp., <SEP> OC <SEP> 320 <SEP> 320 <SEP> 370 <SEP> 350 <SEP> 330 <tb> Contact <SEP> Time, <SEP> sec. <SEP> 12 <SEP> 55 <SEP> 12 <SEP> 13 <SEP> 22 <tb> LHSV <SEP> 0.21 <SEP> 0.21 <SEP> 0.44 <SEP> 0.88 <SEP> 0.21 <tb> Yield <SEP> of <SEP> Morpholine, <SEP> mol. <SEP> X <SEP> 85 <SEP> 63 <SEP> 37 <SEP> 46 <SEP> 75 <tb> Selectivity <SEP> to <SEP> Morpholine <SEP> % <SEP> 85 <SEP> 74 <SEP> 37 <SEP> 57.5 <SEP> 75.6 <tb> Conv. <SEP> of <SEP> DGA <SEP> mol. <SEP> % <SEP> 100 <SEP> 85 <SEP> 100 <SEP> 80 <SEP> 99 <tb> Dioxane <SEP> Yield, <SEP> mol. <SEP> % <SEP> < <SEP> less <SEP> than <SEP> 1% <tb> In each of the Examples 87-91, it was unexpectedly found that DGA could be to selectively converted to morpholine without the conversion of appreciable quantities of dioxane, tar or other high molecular weight components. It would be expected that the reaction product from DGA conversion would contain substantially equal amounts of dioxane and morpholine. Examples 92-118 The test procedure set forth in Examples 87-91 was followed in Examples 92-118 in the presence of the Example 1 catalyst. Table 7 below sets forth the feed mixture, operating conditions and the product yields for each example. TABLE 7 DGA/H2O, Conversion Morpholine Morpholine Example Vol.% Temp. C LHSV Helium Diluent, cc/min. of DGA, mol.% yield, mol.% % Selectivity 92 100/0 370 C 0.44 None 99 36 36 93 100/0 370 C 0.88 None 99 47 47 94 100/0 370 C 1.3 None 94 48 51 95 100/0 350 C 0.44 None 93 47 51 96 100/0 340 C 0.21 None 95 51 54 97 100/0 330 C 0.21 None 100 53 53 98 100/0 320 C 0.88 None 83 43 52 99 80/20 370 C 0.44 None 100 43 43 100 80/20 350 C 0.44 None 93 57 61 101 80/20 350 C 0.44 28.5 100 55 55 102 80/20 340 C 0.67 28.5 93 49 53 103 80/20 330 C 0.44 28.5 95 57 60 104 80/20 330 C 0.31 28.5 100 68 68 105 80/20 325 C 0.21 None 94 47 50 106 80/20 320 C 0.31 28.5 95 73 77 107 80/20 320 C 0.21 28.5 100 81 81 108 80/20 320 C 0.44 28.5 90 46 51 109 80/20 320 C 0.14 28.5 100 73 73 110 80/20 320 C 0.67 None 79 30 38 111 80/20 320 C 0.31 None 86 35 41 112 80/20 310 C 0.44 28.5 82 38 46 113 80/20 320 C 0.31 None 77 46 60 114 50/50 320 C 0.21 None 97 72 74 115 65/35 320 C 0.21 None 98 54 55 116 65/35 330 C 0.31 None 79 50 63 117 35/65 325 C 0.31 None 73 54 74 118 35/65 325 C 0.21 None 100 60 60

Claims: What Is Claimed Is: 1. In methods for the synthesis of organic compounds by condensation reactions in the presence of phosphate catalysts, the improvement which comprises the use as such catalysts which are selected from the group consisting of the pyrophosphate, monohydrogen phosphate and dihydrogen phosphate of strontium, copper, magnesium, calcium, barium, zinc, lanthanum, aluminum, cobalt, nickel, cerium, neodymium, and mixtures thereof. 2. The method as defined in Claim 1 wherein said catalyst is associated with a carrier of the group consisting of silica, alumina and silica-alumina. 3. The method as defined in Claim 1 wherein such condensation reaction is one resulting in the elimination of water. 4. The method as defined in Claim 1 wherein such condensation reaction is one resulting in the elimination of ammonia. 5. The method as defined in Claim 1 or 2 wherein such condensation reaction is one effecting cyclization 6. The method as defined in Claim 1 wherein such condensation reaction comprises the production of triethylenediamine from hydroxyethylpiperazine. 7. The method as defined in Claimed 1 wherein such condensation reaction comprises the production of triethylenediamine from crude hydroxyethylpiperazine. 8. The method as defined in Claim 1 wherein such reaction comprises the production of triethylenediamine from ethanolamines. 9. The method as defined in Claim 1 wherein such condensation reaction comprises the production of triethylenediamine from N-aminoethylpiperazine. 10. The method as defined in Claim 1 wherein such condensation reaction comprises the production of symmetrical and unsymmetrical aliphatic or aromatic amines from an alcohol and an amine or ammonia. 11. The method as defined in Claim 1 wherein such condensation reaction comprises the production of dimethylaminoethylmorpholine. 12. The method as defined in Claim 1 wherein such condensation reaction comprises the production of a morpholine compound selected from the group consisting of morpholine and alkyl morpholine 13. The process of Claims 11 or 12 wherein the conversion takes place in the presence of an inert gas. 14. The method as defined in any of Claims 6, 7, 9, 11 or 12 wherein the reaction is carried out in the presence of water. 15. A method which comprises converting a substituted piperazine compound selected from the group consisting of hydroxyethylpiperazine and aminoethylpiperazine to triethylenediamine at a temperature in the range of about 2850C to 4200C, a pressure in the range of about 0.1 to 1.5 atmospheres, a liquid hourly space velocity of about 0.05 to 1.5 in the presence of a catalyst selected from the group consisting of the pyrophosphate, monohydrogen phosphate and dihydrogen phosphate of strontium, copper, magnesium, calcium, barium, zinc, lanthanum, aluminum, cobalt, nickel, cerium, neodymium, and mixtures thereof. 16. A method which comprises converting hydroxyethylpiperazine to greater than 50 mol.% yield of triethylenediamine at a temperature in the range of about 3400 to 4000C, a pressure in the range of about 0.3 to 1.0 atmospheres, a liquid hourly space velocity of about 0.1 to 0.3 in the presence of a catalyst selected from the group consisting of the monohydrogen phosphate and dihydrogen phosphate of strontium, calcium, magnesium, zinc, mixtures of strontium and barium in the ratio of Sr to Ba of 1 to 5 to 5 to 1 and mixtures of lanthanum and strontium in the ratio of La to Sr of 15 to 1 to 1 to 15. 17. A method which comprises converting a nitrogencontaining compound selected from the group consisting of ammonia, primary and secondary aliphatic amines and aromatic amines to its corresponding symmetrical and unsymmetrical higher molecular weight aliphatic or aromatic amine in the presence of an alcohol at a temperature in the range of about 2850C to 4200C, a pressure in the range of about 0.1 to 1.5 atmospheres, a liquid hourly space velocity of about 0.05 to l.5'in the presence of a catalyst selected from the group consisting of the pyrophosphate, monohydrogen phosphate and dihydrogen phosphate of strontium, copper, magnesium, calcium, barium, zinc, lanthanum, aluminum, cobalt, nickel, cerium, neodymium, and mixtures thereof. 18. A method which comprises selectively converting greater than 50 mol. % of a nitrogen-containing compound selected from the group consisting of ammonia, primary and secondary aliphatic amines and aromatic amines having 1 to 20 cartons per molecule to its corresponding higher molecular weight aliphatic or aromatic amine in the presence of an alcohol having 1 to 20 carbon atoms per molecule in the molar ratio of said nitrogen-containing compound to alcohol in the range of about 6 to 1 to 1 to 6 at a temperature in the range of about 3400C to 4000C, a pressure in the range of about 0.1 to 1.5 atmospheres, a liquid hourly space velocity of 0.1 to 0.3 in the presence of a catalyst selected from the group consisting of the pyrophosphate, monohydrogen phosphate and dihydrogen phosphate of strontium, copper, magnesium, calcium, and barium, lanthanum, and mixtures thereof. 19. A method which comprises converting morpholine and dimethylethanolamine to dimethylaminoethylmorpholine in the presence of water and hydrogen at a temperature in the range of about 2850C to 4200C, a pressure in the range of about 0.1 to 1.5 atmospheres, a liquid hourly space velocity of about 0.05 to 1.5 in the presence of a catalyst selected from the group consisting of the pyrophosphate, monohydrogen phosphate and dihydrogen phosphate of strontium, copper, magnesium, calcium, barium, zinc, lanthanum, aluminum, cobalt, nickel, cerium, neodymium, and mixtures thereof. 20. The method as defined in Claim 19 wherein an inert gas is present during the conversion. 21. A method which comprises converting morpholine and dimethylethanolamine in the molar ratio of morpholine to dimethylethanolamine of about 1 to 3 to 3 to 1 in the presence of water, hydrogen and an inert gas to greater than 50 mol. % yield of dimethylaminoethylmorpholine at a temperature in the range of about 3600C to 4000C, a pressure in the range of about 0.3 to 1.0 atmospheres, a liquid hourly space velocity of about 0.1 to 0.3 in the presence of a mixed nickel and strontium hydrogen phosphate catalyst. 22.. A process which comprises converting a diglycolamine compound to a morpholine compound at a temper ature in the range of about 2850C to 4200C, a pressure in the range of about 0.1 to 1.5 atmospheres, a liquid hourly space velocity of about 0.05 to 1.5 in the presence of a catalyst selected from the group consisting of the pyrophosphate and the monohydrogen and dihydrogen phosphate of strontium, copper, magnesium, calcium, barium, zinc, lanthanum, aluminum, cobalt, nickel, cerium, neodymium, and mixtures thereof. 23. The process of Claims 22 wherein the conversion takes place in the presence of an inert gas 24. The process of Claim 22 wherein said diglycolamine compound is selected from the group consisting of diglycolamine and alkyl diglycolamine and mixtures thereof and said morpholine compound is selected from the group consisting of morpholine and alkyl morpholine and mixtures thereof, wherein each of said alkyl groups contains from 1 to 6 carbon atoms. 25. A process which comprises converting diglycolamine to morpholine at a temperature in the range of about 2850C to 4200C, a pressure in the range of about 0.1 to 1.5 atmospheres, a liquid hourly space velocity of about 0.05 to 1.5 in the presence of a catalyst selected from the group consisting of the pyrophosphate and the monohydrogen and dihydrogen phosphate of strontium, copper, magnesium, calcium, barium, zinc, lanthanum, aluminum, cobalt, nickel, cerium, neodymium, and mixtures thereof. 26. A process which comprises converting diglycolamine to greater than 50 mol.% yield of morpholine and less than 1 mol.% yield of dioxane at a temperature in the range of about 3000 to 3700C, a pressure in the range of about 0.3 to 1.0 atmospheres a liquid hourly space velocity of about 0.1 to 1.0 in the presence of a catalyst consisting essentially of strontium monohydrogen phosphate. 27. The method as defined in Claims 25 or 26, wherein the conversion is carried out in the presence of water. 28. The method as defined in any of Claims 25, 26 or 27 wherein the conversion takes place in the presence of an inert gas.

Inventors: ESKINAZI, VICTORIA, WELLS, JAMES EDWARD
Applicants: AIR PRODUCTS AND CHEMICALS, INC.
Application year: 1982
Main classification: B01J27
IPC codes: C07D295, B01J27, C07D487