TY - DATA T1 - Doubly Cyclometalated Pyridazines:  Contrasting Behavior with Palladium and Platinum PY - 2001/09/11 AU - Jonathan W. Slater AU - Donocadh P. Lydon AU - Nathaniel W. Alcock AU - Jonathan P. Rourke UR - https://acs.figshare.com/articles/journal_contribution/Doubly_Cyclometalated_Pyridazines_Contrasting_Behavior_with_Palladium_and_Platinum/3766491 DO - 10.1021/om010449g.s002 L4 - https://ndownloader.figshare.com/files/5873907 KW - metal source KW - cycloplatination KW - cyclometalation KW - chloride KW - palladium N2 - The cyclometalation of 3,6-diphenylpyridazines with palladium and platinum has been studied. When palladium acetate is used as the metal source, two sequential cyclometalations are observed, with the first cyclometalation deactivating the system toward a second cyclometalation. Both monocyclopalladated and dicyclopalladated species have been isolated and characterized as their acetylacetonate derivatives. When potassium tetrachloroplatinate is used as the metal source, only double cycloplatination is observed:  the first cycloplatination activates the system toward a second cycloplatination through a combination of nitrogen coordination and a chloride bridging two platinums. A doubly cycloplatinated compound has been isolated as its triphenylphosphine derivative, which has been fully characterized:  the single-crystal X-ray structure shows that the two platinums are bridged by a chloride. ER -