A Review of U.S. Patents in the Field of Organic Process Development Published During June and July 2012

摘要

The current review contains 20 patents from an initial list of 238 that fitted the selection criteria. The range of subjects is quite wide with some patents having an extensive amount of chemistry. An example is the synthesis of aliskiren that is used to treat high blood pressure. The molecule has four chiral centres, and the new process gives the product with high stereoselectivity without the need to purify intermediates. Another comprehensive patent describes the synthesis of isoquinolines that are intermediates for a hepatitis C drug. Unusually the patent gives very detailed instructions for the preparation. Another detailed patent describes the synthesis of electronically tuned ligands for asymmetric hydrogenation of a specific molecule. The preparation of optically active quinuclidinols also involves asymmetric hydrogenation and chiral diphosphine amine Ru complexes are used to promote high selectivity. Another asymmetric hydrogenation process is described in the synthesis of hexa-hydroisoquinolines that are used as intermediates in the synthesis of a number of analgesics.