摘要 : A new scorpionate ligand, Na[HB(mim) _2(Pn ~(tBu))] (Na[ ~(Pn)Bm]), with one pyridazinyl-3-thione and two methimazolyl (mim) substituents was prepared by mixing 6-tert-butylpyridazine-3-thione (HPn ~(tBu)) and sodium dihydridobis(... 展开 A new scorpionate ligand, Na[HB(mim) _2(Pn ~(tBu))] (Na[ ~(Pn)Bm]), with one pyridazinyl-3-thione and two methimazolyl (mim) substituents was prepared by mixing 6-tert-butylpyridazine-3-thione (HPn ~(tBu)) and sodium dihydridobis(methimazolyl)borate (Na[Bm]) in boiling xylene. Addition of CuCl to a solution of Na[ ~(Pn)Bm] in methanol in the presence of PR _3 gave the monomeric copper(I) complexes [Cu{ ~(Pn)Bm}(PR _3)] (R = cyclohexyl 1, phenyl 2) in good yields. They were characterized by NMR spectroscopy and in the case of 2 also by single-crystal X-ray diffraction analysis. The latter revealed a compound in which the ligand is coordinated in a κ ~3-S,S,H fashion, exhibiting a 3-center-2-electron B-H·Cu interaction. Reaction of the ligand Na[ ~(Pn)Bm] with CuCl in the absence of phosphane yielded a copper(I) complex, which was determined to be [Cu{ ~(Pn)Bm}] (3). Variable-temperature 1H NMR spectroscopy points to the occurrence of two dimeric isomers in solution, which interconvert in a fluxional behavior at room temperature. DFT calculations show that two isomers with a κ ~3-S ~(mim),S ~(mim),H or a κ ~3- H ~(mim),S ~(Pn),H coordination mode have very similar energies with a low energy barrier (25.4 kJ/mol) for their interconversion. 收起