New Chiral Organo catalysts and Their Application in Asymmetric Aldol Reaction


Yolaçan Ç. , Aydoğan F.

3rd INTERNATIONAL TURKIC WORLD CONFERENCE ON CHEMICAL SCIENCES AND TECHNOLOGIES (3rd ITWCCST) , Baku, Azerbaycan, 10 - 13 Eylül 2017, ss.181

  • Basıldığı Şehir: Baku
  • Basıldığı Ülke: Azerbaycan
  • Sayfa Sayıları: ss.181

Özet

Organocatalysts are easily produced organic molecules which do not contain any metal.They have various advantages over biocatalysts and metal catalysts economically and in terms of green chemistry.They are robust, cheap, non-toxic and the most importantly recyclable.They are not sensitive to water and moisture. They do not require hard reaction conditions such as inert atmosphere and anhydrous solvent1-3. Because of these advantages, enantioselective organocatalytic processes such as carbon-carbon bond forming reactions have been improved and developed in recent years.  

The use of metals in biocatalytic processes is not observed in nature and real life. Scientific authorities focus on new methodologies for metal free synthetic designs by taking into consideration these processes. The biggest interest is towards developing of systems which contain proline skeleton in their structure to use in the formation of asymmetric molecules with carbon-carbon bond formation reactions via enamine such as aldol reactions. Because of the disadvantages of proline such as solubility, excess usage and medium enantioselectivities, it is very important to evaluate modification and catalytic activities of proline skeletons which can provide high activity and selectivity in order to eliminate the disadvantages of proline. The focus has been given to design new catalysts based on L-proline because of its advantages, disadvantages and importance4. 

This study is based on designing and developing of new chiral organocatalysts which have structural diversity tocatalyze asymmetric direct aldol reactions under various reaction conditions. For this purpose, L-Proline based new chiral organocatalysts which have di- and triamidestructure have been synthesized. The structures of these catalysts were determined by FTIR, 1H-NMR, 13C-NMR, Q-TOF spectral data. At the last step, catalytic effects of synthesized organocatalysts in the enantioselective direct aldol reaction were investigated. Good yields and enantioselectivities have been observed with the newly synthesized L-proline based organocatalysts. 

Thisresearch is financiallysupportedbyYildiz Technical UniversityResearch Foundation (Project Number: 2015-01-02-YL09) 

References 

1. E.M.O. Yeboah, S.O.Yeboah, G.S. Singh; Tetrahedron, 2011, 67, 1725-1762. 2. S.Bertelsen, K.A.Jorgensen; RoyalSoc. Chem.,2009, 38, 2178-2189. 3. A. Scettri, A. Massa, L. Palombi, R. Villano, M.R. Acocella; Tetrahedron: Asymmetry,2008,19, 2149-2152. 4. T.P. Kumar, R.C. Shekhar, K.S. Sunder, R.Vadaparthi; Tetrahedron: Asymmetry, 2015, 26, 543–547.