Efficient and selective method for the synthesis of dihydrodipyridopyrazines based on the pd-catalysed animation of halopyridines
A novel methodology for the efficient: and selective synthesis of isomers A and B of N-substituted dihydrodipyridopyrazines was developed. The key step is the intermolecular coupling of aminopyridines and halonitropyridines/dihalopyr- idines in the presen