Synthesis and Reactivity of N-Aminotroponiminatogermylenepyrrole and Its Derivatives

Through the reaction of the aminotroponiminatogermylene monochloride complex [(Bu(2)(i)ATI)GeCl] (1) with sodium pyrrolide, the stable N-germylene pyrrole complex [(Bu(2)(i)ATI)GeNC4H4] (2) has been isolated. The reaction of compound 2 with thiophenol and selenophenol afforded the first germylene thio- and selenophenoidde complexes [(Bu(2)(i)ATI)GeSPh] (3) and [(Bu(2)(i)ATI)GeSePh] (4) through the substitution of the pyrrole moiety (NC4H4) with an EPh moiety (E = S (3), Se (4)), respectively. Interestingly, the chalcogenide derivatives of compound 2, such as the N-germathioacylpyrrole complex [(Bu(2)(i)ATI)Ge(S)NC4H4] (5) and N-germaselenoacylpyrrole complex [(Bu(2)(i)ATI)Ge(Se)NC4H4] (6), also underwent the aforementioned substitution reaction with thiophenol and selenophenol, resulting in the first examples of germa thioester complexes ([(Bu(2)(i)ATI)Ge(S)SPh] (7) and [(Bu(2)(i)ATI)Ge(Se)SPh] (8)) and germa selenoester complexes ([(Bu(2)(i)ATI)Ge(S)SePh] (9) and [(Bu(2)(i)ATI)Ge(Se)SePh] (10)), respectively. All the novel germanium compounds 3-10 have been unequivocally characterized through multinuclear NMR spectroscopy along with the germylene complex 2. Further, compounds 3-5 and 7-10 were characterized through single-crystal X-ray diffraction studies. The Ge-II-S and Ge-II-Se bond lengths in compounds 3 and 4 are 2.367(1) and 2.511(1) angstrom, respectively. The average Ge-IV-S and Ge-IV-Se bond lengths in germa thioester (7 and 8) and germa selenoester (9 and 10) complexes are 2.241(1) and 2.362(1) angstrom, respectively.