872971-32-9Relevant academic research and scientific papers
Interplay between nitrones and (nitrile)PdII complexes: Cycloaddition vs. complexation followed by cyclopalladation and deoxygenation reactions
Bokach, Nadezhda A.,Krokhin, Artem A.,Nazarov, Alexey A.,Kukushkin, Vadim Yu.,Haukka, Matti,Frausto Da Silva, Joao J. R.,Pombeiro, Armando J. L.
, p. 3042 - 3048 (2005)
The reaction between the nitrone P-MeC6H4CH=N(Me)O and trans-[PdCl2(RCN)2] (R = Ph, Me) in the corresponding RCN (or of the nitrone in neat RCN in the presence of PdCl2) proceeds at 45°C (R = Ph) or reflux (R = Me) for 1 d and allows the isolation of the Δ4-1,2,4-oxadiazoline complexes [PdCl2{N a=C(R)ON(Me)CbH(C6H4Me-p)} 2(Na-Cb)] (R = Ph 1; R = Me 2) in ca. 50 and ca. 15 % yields, respectively. The reaction time can be drastically reduced by focused microwave irradiation of the reaction mixture. In CH2Cl 2 or acetone, this reaction proceeds in another direction to achieve the unstable nitrone complex [PdCl2{ON(Me)=CH(C6H 4Me-P)}2] (3), which was characterized by electrospray mass spectrometry, IR and 1H NMR spectroscopy. Complex 3 is the first representative of (nitrone)PdII compounds and is the key in-termediate in at least two further reactions, i.e. cyclopalladation to give the dimeric complex [Pd2(μ-Cl)2{ON(Me)=C(H) C 6H3Me-P}2] (5; 30% isolated yield) and deoxygenation of the nitrone to furnish the imine compound [PdCl 2{N(Me)=CH(C6H4Me-P)}2] (4). The palladium complexes 1, 2, 4 and 5 were characterized by C, H, and N analyses, FAB-MS, IR, 1H and 13C{1H} spectroscopy, while 4 and 5 additionally by X-ray crystallography. Wiley-VCH Verlag GmbH & Co. KGaA, 2005.
