677027-15-5Relevant articles and documents
Synthesis and Reactivity of Four-Membered Azapalladacycles Derived from N,N-Dialkyl-2-iodoanilines: Insertion Reactions of Carbenes into the Carbon-Palladium Bond
Sole, Daniel,Vallverdu, Lluis,Solans, Xavier,Font-Bardia, Merce,Bonjoch, Josep
, p. 1438 - 1447 (2008/10/09)
Three new four-membered azapalladacycles derived from N,N-dialkyl-2-iodoanilines have been synthesized: [Pd(κ 22-C6H4NMe2-2)I(PPh3)] (4a), [Pd{κ2-C6H4N(Me)CH 2Ph-2}I(PPh3)] (4b), and [Pd{κ2-C 6H4N(Me)Pr-2}I(PPh3)] (4c). On heating in solution azapalladacycles 4a and 4c undergo aryl-aryl interchange between the palladium atom and the phosphine ligand to give the phosphanyl-amine palladium complexes [PdPhI(PNMe2)] (7a) and [PdPhI{PN-(Me)Pr}] (7c), respectively. Azapalladacycles 4a-c react with dichlorocarbene to give acyl palladium complexes [Pd{κ2-C(O)C6H 4NMe2-2}I(PPh3)] (8a), [Pd{κ 2-C(O)C6H4N(Me)CH2Ph-2}I(PPh 3)] (8b), and [Pd{κ2-C(O)C6H 4N(Me)Pr-2}I(PPh3)] (8c), respectively. Smooth insertion of N2CHCO2Et into the carbon-palladium bond of azapalladacycles 4a-c results in the formation of the single-insertion products [Pd{κ2-CH(CO2Et)C6H4NMe 2-2}I(PPh3)] (9a), [Pd-{κ2-CH(CO 2Et)C6H4N(Me)CH2Ph-2}I(PPh 3)] (9b), and [Pd{κ2-CH(CO2Et)C 6H4N(Me)Pr-2}-I(PPh3)] (9c), respectively. On the other hand, complexes 4a and 4c react with N2CHTMS to give mainly the single-insertion products [Pd{κ2-CH(SiMe 3)C6H4NMe2-2}I(PPh3)] (10a) and [Pd{κ2-CH(SiMe3)C6H 4N(Me)Pr-2}I(PPh3)] (10c), respectively, while under similar reaction conditions 4b affords N-benzyl-N-methyl-2-[(Z)-2-(trimethylsilyl)vinyl]aniline (11b) as a consequence of a double-insertion process. Solid state structures of palladium complexes 4b, 8b·EtOAc, 9a, 9b, and 9c·Et2O have been determined by X-ray analysis.
