Chiral Quest patents novel chiral catalyst
patent covering the use of novel catalysts to increase the
efficiency of chiral amine and amino acid synthesis.
A lot of chiral phosphine ligands have been explored for practical application in asymmetric catalysis but few have proved to be efficient for the synthesis of chiral molecules at an industrial level. Among the known chiral phosphines, several are made from electron-donating chiral phospholanes.
Technologies to make chiral molecules - i.e. those that consist of just one of the two or more forms of a molecule that is determined by the arrangement of its atoms - are increasingly used in chemical synthesis, particularly in the drug industry where it is preferable to test and produce only one form of a compound.
The new patent, awarded to Chiral Quest's chief technology officer Prof Xumu Zhang, describes a series of catalysts based on chiral phospholanes and hydroxyl phospholanes that, it is claimed, improve on what has gone before.
The use of the new chiral phospholanes (sold under the trade names Ketalphos and f-KetalPhos) results in one of the most efficient syntheses of chiral amines and amino acids, accroding to Chiral Quest, as they offer high activity and enantioselectivity (synthesis of the desired isomeric form) in asymmetric hydrogenation of alkenes.
Another key feature is that the diastereomers of these ligands are derived from the same low-cost source, D-mannitol, and offer the opposite enantioselectivity in asymmetric catalysis.
"The KetalPhos family, hydroxyl phospholanes and their diastereomers can be prepared from common and accessible D-mannitol, making these catalysts very cost-effective," said Prof Zhang.
"Their properties are similar to certain more expensive benchmark ligands in current industrial commercial processes. Members of the KetalPhos family of ligands and catalysts could become an important part of the efficient manufacture of many pharmaceutical and fine chemical products," he added.
Last year, a report published by Frost & Sullivan predicted that the market for chiral compounds destined for the drug industry will rise from $7.0 billion (€6bn) in 2002 to $14.9 billion in 2009. In 2002, 55 per cent of chiral compounds were generated by traditional resolution technologies, 35 per cent by chemocatalysis and 10 per cent by biocatalysis.
