186391-55-9Relevant academic research and scientific papers
Reactions of bis(iminophosphoranes) with palladium(II) dichloride: Metal-induced tautomerization orthopalladation and unexpected platinum-assisted [2 + 2] cycloaddition of an aryl-nitrile with a phosphinimine moiety
Avis, Mandy W.,Van Der Boom, Milko E. Der,Elsevier, Cornelis J.,Smeets, Wilberth J. J.,Spek, Anthony L.
, p. 263 - 276 (2007/10/03)
Reactions of bis(iminophosphoranyl)methane, CH2(PPh2=N-aryl)2, (BIPM; 1a,b) or 1,1-bis(iminophosphoranyl)ethane (1,1-BIPE; 1c) with Pd-and Pt-dichlorides containing weakly coordinating ligands (L) such as nitriles or cyclo-octadiene, afforded several products depending on the reaction time, type of ligand (1a-c) or nature of the metal. The first reaction observed is a metal-assisted tautomerization of BIPM to aryl-N=PPh2-CH=PPh2-NH-aryl. When BIPM reacts with PdCl2(L)2, exclusive formation of the C,N-chelate PdCl2{CH(PPh2=N-aryl)(PPh2-NH-aryl)} (2a,b) is observed, whereas with 1,1-BIPE (1c) a product mixture consisting of a C,N-chelate (2c) and an N,N′-chelate (3) is found. Orthometallation of the four-membered palladacycle (2) took place upon heating, giving the five-membered palladacycle [PdCl2{2-C6H4-PPh(NH[-pTol)-C′H-PPh2(NH-pTol)}-C,C′] (4). The molecular structure of 4 has been determined by X-ray crystallography. Reactions of BIPM (1a,b) with PtCl2(RC≡N)2 (R = phenyl, p-tolyl) afforded entirely different products: the six-membered platinacycles [PtCl(RC≡N){aryl-N=C(R)-N=PPh2-CH=PPb2-NH-aryl}-C,N]Cl (5) and [PtCl2{aryl-N=C(R)-N=PPh2-CH=PPh2-NH-aryl}-C,N] (6), due to an unexpected 2 + 2 cycloaddition of a nitrile with a P=N group.
