US Patent 7619123 Methods for stabilizing lithiated halogen-substituted aromatic compounds

The present invention provides novel methods for stabilizing lithiated halogen-substituted aromatic compounds. In particular, the method is useful for the preparation of 2-methoxy-5,6-difluorobenzaldehyde, an important intermediate for the preparation of [4-amino-2-(1-methanesulfonylpiperidin-4-ylamino)pyrimidin-5-yl](2,3-difluoro-6methoxyphenyl)methanone, a potent and selective inhibitor of CDK4/Cyclin D1, CDK2/Cyclin E and CDK1/Cyclin B. The method is also useful for stabilizing other lithiated halogen-substituted aromatic compounds and is particularly useful for scale up reactions where the exothermic nature of the reaction can lead to reaction runway.