A Spanish-Portuguese research group from the department of Inorganic Chemistry at Alcalá University and ITQB-Universidad Nova of Lisboa of Oeiras, has developed a process of synthesis of titanium silesquioxane compounds and its applications in oxidation catalyst of organic sulphur compounds. The group looks for licencing agreements and commercial or collaboration agreements with pharmaceutical and petrochemical industry, and those industries in charge of the fertilizer preparation and production of compounds for the treatment of environmental problems.
New and innovative aspects
The using of titanium silsesquioxanes as catalysts of oxidation of sulfide groups.
Main advantages of its use
The catalysts are easy to synthesize and in the synthesis process is generated triethylammonium chloride, an inert inorganic salt, as the only byproduct derived therefrom. This salt is easily disposable by filtration.
• The catalysts are resistant to degradation under the conditions of catalysis.
• The titanium catalysts are slightly toxic. According to the International Agency on Cancer Research (IARC), titanium is not classified as a carcinogen element to humans.
• The Catalysis process can be performed without an inert atmosphere.
• The process shows improvements in the selectivity of the process, reaching capacities of a 100% in obtaining the sulfoxide.
• Once the sulfoxide has been generated, the same catalyst can be used for the synthesis of the sulfone.
• The oxidant used, preferably H202, is safe for the environment. Since the byproduct generated is water.
• The conditions of pressure and temperature are easily accessible.
• The procedure is simple, efficient and cheap, since the compound that would represent a higher cost, which is the catalyst, is used in a very low proportion.
The present invention is based on the synthesis of titanium silsesquioxane compounds and its applications in oxidation catalyst of organic sulphur compounds using as oxidant tert-Butyl hydroperoxide and hydrogen peroxide.
In a first aspect, the present invention relates to the synthesis of the catalysts. The general procedure consists in the reaction of the titanium compound 1 with the partially condensed silsesquioxane compound 2 in the presence of a base such as triethylamine all dissolved in an apolar solvent such as toluene.
After twelve hours of reaction at room temperature, compound 3 is obtained
(See figure 1).
When the same reaction is carried out at elevated temperature, 70º during 72 hours the compound 4 is quantitatively obtained (see figure 2).
It’s necessary to carry out the reaction of synthesis of these compounds in an inert atmosphere. Once synthesized they become stable against oxygen and humidity.
The Catalyzing of oxidation of sulphides is the oxidation of the functional sulfide group to the functional sulfoxide group or sulfone, or both. It is carried out in presence of a titanium catalyst and a peroxide as a source of oxygen, that could be TBHP o H2O2. It is used as a solvent, a nonpolar or aprotic medium, if the peroxide is TBHO or a polar or protic medium if the peroxide is H2O2. The process is carried out at atmospheric pressure and room temperature. On the assumption that both oxidation products are obtained, by adding another equivalent of peroxide, the reaction evolves over time toward the maximum oxidation product, which is sulfone.
The products are obtained in high capacity and purity (see figure 3).
- Pharmaceutical, biological and petrochemical companies
- The treatment of environmental problems