Organic compounds -- part of the class 532-570 series – Organic compounds – Carboxylic acid esters
Reexamination Certificate
2000-02-07
2003-10-14
Rotman, Alan L. (Department: 1625)
Organic compounds -- part of the class 532-570 series
Organic compounds
Carboxylic acid esters
C502S103000, C560S248000, C560S252000
Reexamination Certificate
active
06632959
ABSTRACT:
TECHNICAL FIELD
The present invention relates to a base catalyst and to a method for producing a derivative of carbonyl compound using the same. More particularly, the present invention relates to a base catalyst comprising an alkali metal compound selected from the group consisting of alkoxides, hydroxides and oxides of alkali metals and an alkaline-earth metal oxide, and to a method for producing a derivative of carbonyl compound, such as glycol monoesters or the like, from aldehydes using the catalyst.
BACKGROUND ART
Base catalysts are used in synthetic reactions, such as aldol condensation reaction, for producing many kinds of compounds. When reactions are conducted on an industrial scale using base catalysts, there have been widely used alkali metal hydroxides, typically sodium hydroxide, and alkali metal alkoxides, typically sodium methoxide.
However, most of the alkali metal hydroxides and alkoxides act as a homogeneous catalyst in the reaction system and, hence, they require neutralization and washing with water as operations for removing the catalyst after completion of the reaction. This naturally results in the production of a large amount of waste water. In general, homogeneous catalysts produce larger amounts of by-products, so that it is often the case that a selectivity of the product (selectivity of the target product) is lowered.
On the other hand, in Japanese Patent Application Laid-open No 58-65245, a method in which an alkaline-earth metal oxide is used as a solid base catalyst in a method for producing a glycol monoester from an aldehyde with a solid base catalyst is described. However, reactions with barium oxide or magnesium oxide alone, for example, could afford low levels of catalytic activity so that it has been difficult to provide sufficient catalytic activity by using alkaline-earth metal oxides alone.
As described above, with conventional catalyst systems, use of homogeneous catalysts having higher activity has caused a larger amount of waste water whereas use of heterogeneous catalysts has caused only a small amount of waste water, but it has made it difficult to obtain sufficient catalyst activity or product selectivity.
Generally, use of heterogeneous solid catalysts, as compared to homogeneous catalyst reactions, provides the following advantages.
(1) There is no need for such operations as neutralization, washing with water, or the like of the catalyst, resulting in the production of no or much less waste water.
(2) The catalyst can be reused.
(3) Product selectivity is high in most cases.
Therefore, it can be expected that methods which involve use of heterogeneous solid catalysts are simpler in process, less inexpensive in cost for a plant, and higher in yield of the target product as compared with those methods using homogeneous catalysts to obtain the target products. Further, because of generating no or much less waste water as compared with the latter methods using homogeneous catalysts, the former methods not only yield less cost for disposal of waste water but also enable suppression of adverse effects on environment, of which a problem has been arisen recently.
However, as stated above, none of the conventional heterogeneous solid catalysts could present sufficient catalytic activity nor sufficient product selectivity and, hence, a further technical innovation has been needed.
DISCLOSURE OF THE INVENTION
It is an object of the present invention to solve the above-described problems and provide an efficient base catalyst which can be applied to base catalyst reactions generally employed, for example, aldol reaction, Michael addition reaction, Tishchenko reaction and the like and which can produce a target product at high activity and high selectivity.
Previously, the present inventors completed an invention on a method for producing carbonyl compound derivatives using a solid base catalyst comprising barium and calcium (Japanese Patent Application Laid-open No 8-29979) and their further study revealed that use of an alkaline-earth metal oxide which is a conventional solid base catalyst, in combination with a minute amount of an alkali metal compound as catalysts and of a two-step reaction with employing the alkali metal compound as a catalyst in the earlier reaction step and the alkaline-earth metal oxide in the later reaction step increases the catalytic activity, which allows a remarkable decrease in the amount of the catalyst to be used, and an increase in product selectivity, and suppresses generation of waste water to a minimum level, thus completing the present invention.
That is, the base catalyst of the present invention comprises at least one alkali metal compound selected from the group consisting of alkoxides, hydroxides and oxides of alkali metals and an alkaline-earth metal oxide with a weight ratio of the alkali metal compound to the alkaline-earth metal oxide, which is calculated by a formula, “the weight of alkaline metal compound/the weight of alkaline-earth metal oxide”, being from 0.005 to 1.
The method for producing a derivative of carbonyl compound according to the present invention is a method for producing a derivative of carbonyl compound from a carbonyl compound in the presence of a catalyst wherein the catalyst is a catalyst comprising at least one alkali metal compound selected from the group consisting of alkoxides, hydroxides and oxides of alkali metals and an alkaline-earth metal oxide.
Another method for producing a derivative of carbonyl compound according to the present invention comprises an earlier reaction step in which at least one alkali metal compound selected from the group consisting of alkoxides, hydroxides and oxides of alkali metals is used as the catalyst, and a later reaction step in which an alkaline-earth metal oxide is used as the catalyst.
When the reaction is carried out with an alkali metal compound alone as a catalyst, high catalytic activity is obtained while product selectivity is insufficient. In contrast, use of an alkaline-earth metal oxide alone results in a decreased reactivity. The base catalyst of the present invention is a base catalyst which comprises an alkali metal compound and an alkaline-earth metal oxide in combination in a specified weight ratio, can provide high catalytic activity and excellent product selectivity simultaneously and generates less waste water.
Hereafter, embodiments of the present invention will be described.
(1) Base Catalyst
The base catalyst of the present invention comprises an alkali metal compound and an alkaline-earth metal oxide.
The alkali metal compound of the present invention is selected from the group consisting of alkali metal alkoxides, alkali metal hydroxides and alkali metal oxides. The alkali metals include preferably sodium, potassium and lithium but are not limited thereto.
As the alkali metal alkoxides, there can be used those whose alkyl group contains 1 to 12 carbon atoms. Specific examples thereof include sodium methoxide, sodium ethoxide, sodium t-butoxide, potassium methoxide, potassium ethoxide, potassium t-butoxide, lithium methoxide, lithium ethoxide, lithium t-butoxide, etc.
As the alkali metal hydroxides, there can be used, preferably sodium hydroxide, potassium hydroxide, lithium hydroxide, etc. And as the alkali metal oxides, there can be used preferably sodium oxide, potassium oxide, lithium oxide, etc.
The alkaline-earth metals in the alkaline-earth metal oxides of the present invention include magnesium, calcium, barium and strontium, preferably calcium, barium and strontium, particularly preferably barium and strontium, but are not limited thereto. Specific examples of the alkaline-earth metal oxides include calcium oxide, barium oxide and strontium oxide.
The weight ratio of the alkali metal compound to the alkaline-earth metal oxide in the base catalyst of the present invention is such that alkali metal compound/alkaline-earth metal oxide=0.005 to 1, preferably, 0.01 to 0.5 (weight ratio). When this ratio is too small, the catalytic activity of the base catalyst as a whole tends to become low, whereas
Inui Kan-ichiro
Kawamura Sakae
Kurabayashi Toru
Oshima Shunji
Yokota Masahiro
Chisso Corporation
Oh Taylor V.
Rotman Alan L.
Wenderoth , Lind & Ponack, L.L.P.
LandOfFree
Basic catalysts and process for producing carbonyl compound... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Basic catalysts and process for producing carbonyl compound..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Basic catalysts and process for producing carbonyl compound... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3166533