Guanidine, (ArNH)2C=NAr (Ar = 2-(MeS)C6H4) was prepared in 70 (method 1)/92 (method 2) yields. Cyclopalladation of the guanidine with Pd(OC(O)R)2 (R = Me and tBu) afforded the CNS pincer complexes, Pd{κ~3(C,N,S)}(OC(O)R) in 82 and 75 yields, respectively. Pd{κ~3(C,N,S)}(OC(O)R) (R = Me and ~tBu) upon metathesis reaction with LiBr gave Pd{κ~3(C,N,S)}Br in 67 and 72 yields, respectively. The reaction of Pd{k~3(C,N,S)} Br with AgBF4 in MeCN gave Pd{κ~3(C,N,S)}(MeCN)BF4 in 82 yield. The new compounds were characterised by elemental analysis, IR and NMR spectroscopies and mass spectrometry. Molecular structures of (ArNH)2C=NAr (Ar = 2-(MeS)C6H4) and Pd{κ~3(C,N,S)}(OC(O)~tBu) were determined by single crystal X-ray diffraction while the solution behaviour of the former compound studied by VT ~1H NMR spectroscopy. Pd {κ~3(C,N,S)}(OAc) was used as a catalyst in Suzuki-Miyaura coupling reactions of aryl bromides with aryl boronic acids.
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