Phosphine oxides bearing two or three 2‐pyridyl groups react with organometallic reagents affording 2,2′‐bipyridyl, 2‐substituted pyridines and pyridine in good yields. Phosphonium salts and phosphine oxides, bearing at least two 2‐pyridyl or substituted 2‐pyridyl groups also give the corresponding 2,2′‐bipyridyls and pyridines upon treatment with acid or neutral solvents such as water and alcohols in substantial yields. The 2,2′‐bipyridyls are considered to be formed by ligand coupling within the pentacoordinated phosphorus intermediate formed incipiently during the reaction.
When tris(2‐pyridyl)phosphine oxide (I) is treated with organometallic reagents such as the Grignard compounds (II), the bipyridine (III) is obtained as the main product, together with pyridine (IV) and only small amounts of the 2‐substituted pyridines (V).
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.