54356-26-2Relevant articles and documents
BIPHENYLENES AND HETEROCYCLIC ANALOGUES OF BIPHENYLENE. PART IV. ELECTROPHILIC AND NUCLEOPHILIC REACTIONS AND BASICITIES OF 1,6-, 1,8-, AND 2,7-DIAZABIPHENYLENES.
MacBride, J. A. Hugh,Wright, Peter M.
, p. 3001 - 3018 (2007/10/02)
The basicities of three diazabiphenylenes (DABPs) and the relative complexing ability of the nitrogen atoms of 1,6-DABP correspond with the postulated increase in effective electronegativity of the ring-junction carbon atoms associated with re-hybridisation.The mono-N-oxide of 2,7-DABP is obtained using m-chloroperbenzoic acid and gives 3-chloro-2,7-DABP with phosphoryl chloride; the structures of these compounds are confirmed by formation of O- and N-methyl iodides respectively.Thiophosgene and base opens one pyridine ring of 2,7-DABP while sodium hydroxide opens the 4-membered ring of each of the three DABPs giving pyridyl-pyridones. 2,7-DABP forms a putative N-nitro-derivative with nitronium tetrafluoroborate and a 1:1 adduct with o-phenylene di-isothiocyanate.A mixed Ullmann reaction between 2-chloro- and 4-chloro-3-nitropyridines gives a minor amount of 3,3'-dinitro-2,4'-bipyridyl which furnishes 1,6-DABP after reductive cyclisation and flash vacuum pyrolytic extrusion of dinitrogen.
