A kind of preparation method of ferrocene bisphosphine-rhodium (I) chiral catalyst

Abstract

The invention discloses a preparation method of a ferrocene diphosphine-rhodium (I) chiral catalyst, and belongs to the field of organic synthesis, particularly relates to the preparation method of the ferrocene diphosphine-rhodium (I) chiral catalyst and aims at solving the problems of low yield, higher sensitivity to air and low yield by asymmetric hydrogenation of the method of preparing a chiral catalyst at present. The preparation method comprises the following steps: adding a ferrocene solution obtained in step two in a bi-(1,5-cyclooctadiene) rhodium tetrafluoroborate (I) solution obtained in step one dropwise under inert gas shielding, adding ether in a filtrate dropwise to precipitate out a catalyst after reaction is finished, washing the catalyst with an organic solvent after filtering, and finally carrying out vacuum drying to obtain the ferrocene diphosphine-rhodium (I) chiral catalyst. The catalyst is simple in preparation step, better in air stability and liable in operation and industrialization, is mainly used for asymmetric hydrogenation catalysis and is higher in enantiomer-selectivity.

Description

technical field

[0001] The invention belongs to the field of organic synthesis, in particular to a preparation method of a ferrocene bisphosphine-rhodium (I) chiral catalyst. Background technique

[0002] Asymmetric catalytic hydrogenation is the most effective way to obtain chiral compounds in asymmetric synthesis. An important goal in the research process is to obtain chiral catalysts with high reactivity and selectivity by designing new chiral catalysts and optimizing reaction conditions. In the past 30 years, a large number of hand catalysts have been synthesized and applied in asymmetric hydrogenation, and many excellent catalysts in asymmetric hydrogenation synthesis have been successfully used in industrial production. For example, the rhodium catalyst of FerroPhos reported by Knochel has a good effect in the catalytic hydrogenation of dehydrogenated amino acids, and achieved an enantioselectivity of 96% ee for the hydrogenation reaction of allyl groups. Fu introduce...

Examples

specific Embodiment approach 1

[0015] Specific embodiment one: the preparation method of a kind of ferrocene bisphosphine-rhodium (I) chiral catalyst of the present embodiment is carried out according to the following steps:

[0016] 1. Dissolving bis(1,5-cyclooctadiene)rhodium(I) tetrafluoroborate in dichloromethane to obtain bis(1,5-cyclooctadiene)rhodium(I) tetrafluoroborate solution;

[0017] 2. Ferrocene is dissolved in methylene chloride to obtain a ferrocene solution;

[0018] The ferrocene is 1,1'-bis(diarylphosphino)ferrocene or 1,1'-bis(dialkylphosphino)ferrocene;

[0019] 3. Under the protection of an inert gas, add the ferrocene solution obtained in step 2 dropwise to the bis(1,5-cyclooctadiene)rhodium(I) tetrafluoroborate solution obtained in step 1, and the reaction time is 2h~4h , filter after the reaction to obtain the filtrate;

[0020] Four, in the filtrate that step 3 obtains, add dropwise diethyl ether to separate out catalyst, then filter out catalyst under the protection of inert gas...

specific Embodiment approach 2

[0021] Specific embodiment two: the difference between this embodiment and specific embodiment one is: bis (1,5-cyclooctadiene) tetrafluoroborate rhodium (I) solution described in step one The concentration of diene) rhodium tetrafluoroborate (I) is 8mmol / L-12mmol / L. Other steps and parameters are the same as those in the first embodiment.

specific Embodiment approach 3

[0022] Embodiment 3: The difference between this embodiment and Embodiment 1 or 2 is that the concentration of ferrocene in the ferrocene solution in step 2 is 15mmol / L-25mmol / L. Other steps and parameters are the same as those in Embodiment 1 or 2.

technical field

[0001] The invention belongs to the field of organic synthesis, in particular to a preparation method of a ferrocene bisphosphine-rhodium (I) chiral catalyst. Background technique

[0002] Asymmetric catalytic hydrogenation is the most effective way to obtain chiral compounds in asymmetric synthesis. An important goal in the research process is to obtain chiral catalysts with high reactivity and selectivity by designing new chiral catalysts and optimizing reaction conditions. In the past 30 years, a large number of hand catalysts have been synthesized and applied in asymmetric hydrogenation, and many excellent catalysts in asymmetric hydrogenation synthesis have been successfully used in industrial production. For example, the rhodium catalyst of FerroPhos reported by Knochel has a good effect in the catalytic hydrogenation of dehydrogenated amino acids, and achieved an enantioselectivity of 96% ee for the hydrogenation reaction of allyl groups. Fu introduce...

Examples

specific Embodiment approach 1

[0015] Specific embodiment one: the preparation method of a kind of ferrocene bisphosphine-rhodium (I) chiral catalyst of the present embodiment is carried out according to the following steps:

[0016] 1. Dissolving bis(1,5-cyclooctadiene)rhodium(I) tetrafluoroborate in dichloromethane to obtain bis(1,5-cyclooctadiene)rhodium(I) tetrafluoroborate solution;

[0017] 2. Ferrocene is dissolved in methylene chloride to obtain a ferrocene solution;

[0018] The ferrocene is 1,1'-bis(diarylphosphino)ferrocene or 1,1'-bis(dialkylphosphino)ferrocene;

[0019] 3. Under the protection of an inert gas, add the ferrocene solution obtained in step 2 dropwise to the bis(1,5-cyclooctadiene)rhodium(I) tetrafluoroborate solution obtained in step 1, and the reaction time is 2h~4h , filter after the reaction to obtain the filtrate;

[0020] Four, in the filtrate that step 3 obtains, add dropwise diethyl ether to separate out catalyst, then filter out catalyst under the protection of inert gas...

specific Embodiment approach 2

[0021] Specific embodiment two: the difference between this embodiment and specific embodiment one is: bis (1,5-cyclooctadiene) tetrafluoroborate rhodium (I) solution described in step one The concentration of diene) rhodium tetrafluoroborate (I) is 8mmol / L-12mmol / L. Other steps and parameters are the same as those in the first embodiment.

specific Embodiment approach 3

[0022] Embodiment 3: The difference between this embodiment and Embodiment 1 or 2 is that the concentration of ferrocene in the ferrocene solution in step 2 is 15mmol / L-25mmol / L. Other steps and parameters are the same as those in Embodiment 1 or 2.