102249-55-8Relevant articles and documents
Reactivity of Some 3-Substituted Derivatives of 2,6-Dihalogenopyridines Towards Potassium Amide in Liquid Ammonia .
Streef, J. W.,Hertog, H. J. den,Plas, H. C. van der
, p. 985 - 991 (2007/10/02)
Reactions of 2,6-dichloro-3-phenyl-, 2,6-dibromo-3-phenyl-, 2,6-dichloro-3-dimethylamino- and 2,6-dibromo-3-dimethylaminopyridine with potassium amide in liquid ammonia were investigated.Whereas 2,6-dichloro-3-phenylpyridine yields 4-amino-2-benzylpyrimidine, from 2,6-dibromo-3-phenylpyridine as a product of a novel ring fission 2-amino-1-cyano-1-phenyl-but-1-en-3-yne was isolated, together with 4-amino-6-bromo-3-phenylpyridine and 2,6-diamino-3-phenylpyridine.It was shown that neither 2-amino-6-bromo-3-phenyl- nor 6-amino-2-bromo-3-phenylpyridine are intermediates in the formation of the 2,6-diamino derivative, as these bromo compounds are transformed in the basic medium into 1,3-dicyano-1-phenylpropene.From both 2,6-dichloro-3-dimethylamino- and 2,6-dibromo-3-dimethylaminopyridine mixtures are obtained from which only 2-amino-1-cyano-1-dimethylamino-but-1-en-3-yne and 4-amino-6-halogeno-3-dimethylaminopyridine were isolated.Mechanisms for the reactions studied are proposed, i.e. a SN(ANRORC) mechanism for the aminodebromination of 2,6-dibromo-3-phenylpyridine into the corresponding 2,6-diamino compound.
