ZA200501915B - Method for producing chlorotris(triphenylphosphine) rhodium (I) - Google Patents
Method for producing chlorotris(triphenylphosphine) rhodium (I) Download PDFInfo
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- ZA200501915B ZA200501915B ZA200501915A ZA200501915A ZA200501915B ZA 200501915 B ZA200501915 B ZA 200501915B ZA 200501915 A ZA200501915 A ZA 200501915A ZA 200501915 A ZA200501915 A ZA 200501915A ZA 200501915 B ZA200501915 B ZA 200501915B
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- South Africa
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- approximately
- solution
- rhodium
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- heated
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- 238000004519 manufacturing process Methods 0.000 title claims description 11
- QBERHIJABFXGRZ-UHFFFAOYSA-M rhodium;triphenylphosphane;chloride Chemical compound [Cl-].[Rh].C1=CC=CC=C1P(C=1C=CC=CC=1)C1=CC=CC=C1.C1=CC=CC=C1P(C=1C=CC=CC=1)C1=CC=CC=C1.C1=CC=CC=C1P(C=1C=CC=CC=1)C1=CC=CC=C1 QBERHIJABFXGRZ-UHFFFAOYSA-M 0.000 title claims 2
- RIOQSEWOXXDEQQ-UHFFFAOYSA-N triphenylphosphine Chemical compound C1=CC=CC=C1P(C=1C=CC=CC=1)C1=CC=CC=C1 RIOQSEWOXXDEQQ-UHFFFAOYSA-N 0.000 claims description 60
- 239000000725 suspension Substances 0.000 claims description 45
- 239000000243 solution Substances 0.000 claims description 39
- 238000000034 method Methods 0.000 claims description 25
- KFZMGEQAYNKOFK-UHFFFAOYSA-N isopropyl alcohol Natural products CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 claims description 24
- 230000008569 process Effects 0.000 claims description 24
- 239000010948 rhodium Substances 0.000 claims description 22
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 21
- 238000001816 cooling Methods 0.000 claims description 14
- MHOVAHRLVXNVSD-UHFFFAOYSA-N rhodium atom Chemical compound [Rh] MHOVAHRLVXNVSD-UHFFFAOYSA-N 0.000 claims description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 14
- 239000013078 crystal Substances 0.000 claims description 13
- 238000010992 reflux Methods 0.000 claims description 13
- 229910052703 rhodium Inorganic materials 0.000 claims description 13
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 claims description 7
- 239000000203 mixture Substances 0.000 claims description 7
- 238000001914 filtration Methods 0.000 claims description 5
- 238000004064 recycling Methods 0.000 claims description 5
- XYFCBTPGUUZFHI-UHFFFAOYSA-N Phosphine Chemical compound P XYFCBTPGUUZFHI-UHFFFAOYSA-N 0.000 claims description 3
- 230000001476 alcoholic effect Effects 0.000 claims description 3
- 239000002244 precipitate Substances 0.000 claims description 3
- 239000000376 reactant Substances 0.000 claims description 3
- 239000005922 Phosphane Substances 0.000 claims 1
- 239000007983 Tris buffer Substances 0.000 claims 1
- 229910000064 phosphane Inorganic materials 0.000 claims 1
- 229960004592 isopropanol Drugs 0.000 description 12
- 238000009835 boiling Methods 0.000 description 10
- 238000006243 chemical reaction Methods 0.000 description 9
- 238000010438 heat treatment Methods 0.000 description 9
- 239000007789 gas Substances 0.000 description 8
- 239000000047 product Substances 0.000 description 7
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 6
- 230000007704 transition Effects 0.000 description 6
- 239000012528 membrane Substances 0.000 description 5
- 239000003208 petroleum Substances 0.000 description 5
- 239000007787 solid Substances 0.000 description 5
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 4
- 239000002904 solvent Substances 0.000 description 4
- 229910052786 argon Inorganic materials 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000003786 synthesis reaction Methods 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 238000005406 washing Methods 0.000 description 2
- YJTKZCDBKVTVBY-UHFFFAOYSA-N 1,3-Diphenylbenzene Chemical group C1=CC=CC=C1C1=CC=CC(C=2C=CC=CC=2)=C1 YJTKZCDBKVTVBY-UHFFFAOYSA-N 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000010790 dilution Methods 0.000 description 1
- 239000012895 dilution Substances 0.000 description 1
- 239000012065 filter cake Substances 0.000 description 1
- 230000007775 late Effects 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 229910000073 phosphorus hydride Inorganic materials 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- CUGZEDSDRBMZMY-UHFFFAOYSA-N trihydrate;hydrochloride Chemical compound O.O.O.Cl CUGZEDSDRBMZMY-UHFFFAOYSA-N 0.000 description 1
Description
Consequently, the invention relates to a process for the production of chlorotris(triphenyl phos- phane) rhodium(l) by reacting RhCl; solution with triphenyl phosphine in mixtures of a C,-Cs alcohol with water, subsequent cooling and filtering of the crystalline precipitate obtained, the mixture of the reactants being treated in such a way that
A it is heated in a first stage to approximately 30°C,
B heated further in a second stage from approximately 30 to approximately 75°C, c maintained at 80 to 110°C.
Stage A can be omitted if the mixture is already at 30°C or warmer (compare practical example 1). Stages A and B can pass into each other if, for example, heating is effected over a period of 3/2 h to several hours starting out from room temperature (compare practical example 3). As can be learned from the practical examples, the temperature indication “approximately 30°C” relates to a temperature range of 25 to 35°C. The indication “approximately 75°C” similarly re- lates to a temperature range situated between 68 and 79°C in which, in the process according to the invention, the transition point is usually situated in the direction towards a dark red solu- tion, which indicates that the reaction has taken place in full. Moreover, the lower temperature limit needs to be reduced to 78°C in step C when ethanol is used as the solvent.
Preferably, the duration of the individual stages is as follows: A approximately 2-1 h, B ap- proximately 1 — 4 h and C approximately ¥2 - 1 h. In this respect, the limits should be considered as flexible, i.e. e.g. +/- 10 minutes in the case of half an hour and +/- 30 minutes in the case of 4 hours. However, an attempt will be made not to excessively prolong the period of the stages for economic reasons.
A process for the production of chlorotris(triphenyl phosphane) rhodium(l) is particularly pre- ferred in the case of which - a solution of RhCl; in water is prepared or a RhCl; solution from a recycling process is made available, - the solution is combined with a C,-Cs alcohol, preferably isopropanol, if necessary under a blanketing gas and/or with cooling (e.g. in an ice bath), - triphenyl phosphine is added if necessary as an alcohol solution or suspension in excess, if necessary again with cooling,
A the mixture or suspension obtained is heated in a first stage from approximately 5 to 20 to approximately 30°C,
B heated further in a second stage from approximately 30 to approximately 75°C,
C maintained at 80 to 110°C or, if necessary, boiled under reflux, - the solution obtained is cooled, - the crystals precipitated out are filtered, washed with the alcohol and/or water and/or petro- leum ether and subsequently dried.
Preferably heating is carried out so slowly in step B that the colour change of the solution to dark red takes place at as high a temperature as possible, preferably at approximately 75°C.
This colour change indicates the reaction to chlorotris(triphenyl phosphane) rhodium(l) which is obtained as dark red crystals later on. In the case of rapid heating of the suspension in step B, the colour change takes place as early as at approximately 60°C. Later on, crystals are then formed during cooling which are so small that the filter aids such as frits become blocked or the crystals cannot be retained by the filter. If the temperature is controlled in such a way that, ini- tially, heating is carried out for sometime (in the case of batches in the 100 g region for ¥2 h) from room temperature (18 to 20°C) to approximately 30°C, then in a further stage for approxi- mately 3 h from approximately 30 to 75°C, the colour change takes place only at approximately 75°C. The resulting crystals have a reproducibly satisfactory size to be able to be filtered without problems and satisfy the requirements and specifications of the catalyst user also as regards the purity.
In a preferred embodiment of the process, the RhCl; is used in the form of an aqueous solution from a recycling process. Surprisingly enough, the quality of the crystals obtained is influenced in this way. The part played by the water appears to be decisive in this respect. Triphenyl phosphine dissolves in isopropanol but is almost insoluble in water. The solubility of triphenyl phosphine is reduced by the dilution effect on addition of an approximately 10% aqueous RhCl; solution. This is illustrated in practical example 3 according to which satisfactorily filterable crystals satisfying the specification can be produced in a high yield.
As an alternative, it can prove to be advantageous not to dissolve triphenyl phosphine com- pletely in alcohol but to use it as an alcoholic suspension. Triphenyl phosphine does in fact not dissolve completely immediately at low temperatures but dissolves slowly only at rising tem- peratures and becomes available for the reaction with RhCl; only then. As a result of this effect, the molar ratio between RhCl; and triphenyl phosphine differs from the quantities introduced and in this case, too, the crystal size is again influenced in a surprisingly advantageous manner by the initial darth of triphenyl phosphine.
Consequently, the invention also relates to a process for the production of chlorotris(triphenyl phosphane) rhodium(l) in the case of which
- a solution of RhCl; in water is produced or a RhCl; solution from a recycling process is made available, - isopropanol is provided under a blanketing gas, - the RhCI; solution is added - triphenyl phosphine is added in excess as an alcoholic suspension,
A the suspension obtained is heated in a first stage from approximately 20 to approximately to 30°C,
B in a further stage heated from approximately 25 to 30 to approximately 75°C,
C boiled under reflux at 80 to 110°C, - the solution obtained is cooled, - the crystals precipitated out are filtered, washed with the alcoho! and/or water and/or petro- leum ether and subsequently dried.
An advantage of an embodiment of the process consists in that the entire synthesis can take place within a single day if the reaction described in practical example 4 is begun at room tem- perature without prior cooling of the solvent. In practice, this proves to be a considerable eco- nomic advantage.
During working up, it has also proved to be an advantage to cool the solution actively after stage C. Surprisingly enough, this has no unfavourable effect on the crystal size and provides a major advantage as a result of the time savings in comparison with the energy expended on cooling.
Moreover, it is possible to achieve an improved space — time yield by limiting the amount of sol- vent as described in sample 5. Smaller crystals which may be formed in the case of this method can be filtered by means of a suction filter in such a way that, overall, a highly economic proc- ess is obtained in the case of the production of larger quantities.
Moreover, the drying process of the crystalline product can be optimised by washing with iso- propanol and, if necessary, petroleum benzine. As a result, drying times of only one day are possible on an industrial scale.
The following examples serve the purpose of illustrating the invention without restricting it.
Yields are indicated in %, based on the rhodium used.
Examples: Comparative example: State of the art, Wilkinson specification
Synthesis according to Inorg. Synth 10, 67 (1967) and, in an identical manner, Inorg. Synth 28, 77 (1990) 2 g of (rhodium(ill) chloride trihydrate are dissolved in 70 ml of ethanol in a 500 ml round bot- tomed flask with a gas inlet line, reflux condenser and gas discharge. A solution of 12 g of triphenyl phosphine freshly recrystallised from EtOH in 350 ml of hot ethanol is added and the flask is rinsed with nitrogen. The solution is boiled under reflux for two hours and the crystalline product is filtered from the hot solution on a frit. After washing with small portions of 50 ml of anhydrous ether, 6.25 g (yield: 88 % based on Rh) are obtained.
Example 1: Wilkinson specification with a temperature control of stage B and C according to the invention
Equipment 1 and 2: round bottomed flask with a gas inlet, reflux condenser and gas discharge. 24 g (0.0916 mole) of triphenyl phosphine are introduced into equipment 2 under argon and dis- solved in the hot state in 700 ml of ethanol. The entire triphenyl phosphine has dissolved at a temperature of only 40°C.
In the meantime, 4 g (0.0158 mole) of RhCl; hydrate are introduced into equipment 1 and sus- pended in 140 ml of ethanol. The triphenyl phosphine solution at 40°C is then added to the red- dish brown suspension under argon through-flow. A dark red solution with a temperature of 36°C is formed. The solution is then slowly heated to boiling point.
Temperature Heating Time Observation 36 -62°C 55 min Orange suspension 62 -67°C 25 min The suspension becomes gradually darker and changes colour to wine red via brown 67°C The reaction has taken place, a dark wine red suspen- sion has formed (transition point) 67 —-79°C 70 min Dark wine red suspension 79 — 80°C Beginning of boiling process, the suspension is boiled for 2 h under reflux
The suspension obtained is cooled to 20°C by means of an ice bath and subsequently filtered through a G3 frit. The wine red product is washed with 2 x 50 ml of ethanol each on the frit and dried in a membrane pump vacuum. 14.549 g of wine red solid were obtained. The calculated yield is 99.2%.
Example 2 4 g of Rh (0.0389 mole) in the form of an aqueous RhCl; solution with a rhodium content of 23% are dissolved in 490 ml of isopropanol under argon in a round bottomed flask with a gas inlet and outlet and a reflux condenser and cooled to 5°C by means of an ice bath.
At this temperature, 50 g (0.191 mole) of triphenyl phosphine are added with stirring and the suspension is subsequently slowly heated to boiling point.
Temperature Heating Time Observation 5°C Dark reddish brown solution with undissolved triphenyl phosphine — 31°C 1h Brown suspension 25-70°C 3.25h Orange suspension 70 ~ 75°C 30 min The suspension becomes gradually darker and changes colour to wine red via brown 75°C The reaction has taken place, a wine red suspension has formed (transition point) 75-79°C 15 min Wine red suspension 79 - 80°C Beginning of the boiling process, the suspension is boiled for 1 h under reflux
The suspension obtained is allowed to cool overnight without active cooling. Next day, cooling to 10°C is carried out by means of an ice bath and subsequently, filtration takes place on a G3 frit. The product is additionally washed on the frit with 235 ml of isopropanol and 100 ml of pe- troleum benzine and dried in the membrane pump vacuum. 35.81 g (0.0387 mole) of wine red finely crystalline solid are obtained.
So 7
The calculated yield is 99.4%.
Example 3 4 g of Rh (0.0389 mole) in the form of RhCl; hydrate (Rh content 40.7%) are dissolved in 26 ml of fully demineralised water overnight one day before the actual synthesis. 490 ml of isopropa- nol are introduced into a round bottomed flask with a gas inlet and outlet and a reflux con- denser. The RhCI; solution is then added. Then 50 g (0.191 mole) of triphenyl phosphine are added and the suspension is subsequently heated slowly to boiling point.
Temperature Heating Time Observation 21°C Brown suspension 25-70°C 4h Orange suspension 70-75°C 40 min The suspension becomes gradually darker and changes colour to wine red via brown 75°C The reaction has taken place, a wine red suspension has formed (transition point) 75-79°C 25 min Wine red suspension 79 - 80°C Beginning of the boiling process, the suspension is boiled for 1 h under reflux
The suspension obtained is allowed to cool overnight without active cooling. Next day, cooling to 20°C is carried out by means of an ice bath and subsequently filtration takes place on a G3 frit. The product is additionally washed on the frit with 405 ml of fully demineralised water and 235 ml of isopropanol. Subsequently, the filter cake is dried in the membrane pump vacuum. 35.82 g of wine red finely crystalline solid were obtained.
The calculated yield is 99.4%.
Example 4 4 g of Rh (0.0389 mole) in the form of the aqueous RhCI; solution with an Rh content of 23%, are diluted with water to an Rh content of 10%. 490 ml of isopropanol are combined with the RhCl; solution. Then 50 g (0.191 mole) of triphenyl phosphine are introduced into the flask and heated stepwise to boiling point.
Temperature Heating Time Observation 19°C Dark reddish brown solution with undissolved triphenyl! phosphine -30°C 30 min Brown suspension 30-74°C 3.25h Orange suspension 74 -78°C 30 min The suspension becomes gradually darker and changes colour to wine red via brown 78°C The reaction has taken place, a wine red suspension has formed (transition point) 75-79°C 15 min Wine red suspension 79 - 80°C Beginning of the boiling process, the suspension is boiled for 1 h under reflux
The suspension obtained is cooled to 20°C by means of an ice bath and subsequently, filtered on a G3 frit. The product is additionally washed on the frit with 235 ml of isopropanol and 100 ml of petroleum benzine and dried in the membrane pump vacuum. 35.47 g of wine red finely crystalline solid are obtained.
The calculated yield is 98.5%.
Example 5 (Repetition of example 4 though with 30% less solvent and water) 343 ml of isopropanol and 4 g of Rh in the form of the RhCI3 solution with an Rh content of 10% are introduced together with triphenyl phosphine into the flask and heated stepwise from room temperature to boiling point in the same way as in example 4.
Temperature Heating Time Observation 19°C Dark reddish brown solution with undissolved triphenyl phosphine 26 - 34°C 45 min Brown suspension
<0 9 34 - 68°C 3h Orange suspension 68 — 75°C 45 min The suspension becomes gradually darker and changes colour to wine red via brown 75°C The reaction has taken place, a wine red suspension has formed (transition point) 75-79°C 15 min Wine red suspension 79 - 80°C Beginning of the boiling process, the suspension is boiled for 1 h under reflux
The suspension obtained is cooled to 20°C by means of an ice bath and subsequently filtered on a G3 frit. The product is additionally washed on the frit with 235 ml of isopropanol and 100 mi of petroleum benzine and dried in the membrane pump vacuum. 34.44 g of wine red finely crystalline solid are obtained.
The calculated yield is 95%.
Claims (7)
1. Process for the production of chiorotris(triphenyl phosphane)-rhodium(l) by reacting RhCl; solution with triphenyl phosphine, subsequent cooling and filtering the crystalline precipi -tate obtained, wherein the mixture of the reactants is treated in such a way that A it is heated in a first stage to approximately 30°C, B heated further in a second stage from approximately 30 to approximately 75°C, Cc maintained at 80 to 110°C.
2. Process for the production of chlorotris(triphenylphosphine)-rhodium(l) by reacting RhCls solution with triphenyl phosphine, subsequent cooling and filtering the crystalline precipi- tate obtained, wherein a mixture of the reactants at 30 to 40°C is treated in such a way that B it is heated up from approximately 30 to 40°C to approximately 75°C, Cc maintained at 80 to 110°C.
3. Process for the production of chlorotris(triphenyl phosphane) rhodium(l) wherein - a solution of RhCls in water is prepared or a RhCl; solution from a recycling process is made available, - the solution is combined with a C,-Cs alcohol, if necessary with cooling, - triphenyl phosphine is added in excess, if necessary with cooling. A the suspension obtained is heated in a first stage from approximately 5 to 20 to approxi mately 30°C, 8 heated further in a second stage from approximately 30 to approximately 75°C, Cc maintained at 80 to 110°C. - the solution obtained is cooled, - the crystals precipitated out are filtered, washed and subsequently dried.
4. Process for the production of tris(triphenyl phosphine) rhodium(1) chlorotris(tripheny! phos- phane) rhodium(l) wherein AMENDED SHEET SSR/SJ/SI20005004197
I. - a solution of RhCl, in water is prepared or a RhCls solution from a recycling process is made available, - isopropanol is provided under a blanketing gas, - the RhCl; solution is added, - triphenyl phosphine is added in excess as an alcoholic solution or suspension, A the mixture obtained is heated in a first stage from approximately 20 to approximately 30°C, B heated further in a second stage from approximately 30 to approximately 75°C, C boiled under reflux at 80 to 110°C. - the solution obtained is cooled, - the crystals precipitated out are filtered, washed with alcohol and/or water and/or pe- troleum ether and subsequently dried.
S. Process according to any one of claims 1 to 4 wherein the stages A last for approximately 2 to 1h, Bfor1to4handC for approximately ¥2 to 1 h.
6. Process according to the invention for the production of chlorotris(triphenyl phosphane) rhodium (1), substantially as hereinbefore described or exemplified.
7. Process for the production of chlorotris(triphenyl phosphane) rhodium (1) including any new and inventive integer or combination of integers, substantially as herein described. AMENDED SHEET SSR/SJISII20005004197
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| ZA200501915A ZA200501915B (en) | 2005-03-07 | 2005-03-07 | Method for producing chlorotris(triphenylphosphine) rhodium (I) |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| ZA200501915A ZA200501915B (en) | 2005-03-07 | 2005-03-07 | Method for producing chlorotris(triphenylphosphine) rhodium (I) |
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| Publication Number | Publication Date |
|---|---|
| ZA200501915B true ZA200501915B (en) | 2007-01-31 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| ZA200501915A ZA200501915B (en) | 2005-03-07 | 2005-03-07 | Method for producing chlorotris(triphenylphosphine) rhodium (I) |
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| ZA (1) | ZA200501915B (en) |
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- 2005-03-07 ZA ZA200501915A patent/ZA200501915B/en unknown
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