Transition‐Metal Chemistry of Alkaline‐Earth Elements: The Trisbenzene Complexes M(Bz)3 (M=Sr, Ba). Issue 48 (17th October 2019)

• Record Type: Journal Article
• Authors: Wang, Qian; Pan, Sudip; Wu, Yan‐Bo; Deng, Guohai; Bian, Jian‐Hong; Wang, Guanjun; Zhao, Lili; Zhou, Mingfei; Frenking, Gernot
• Is Part Of: Angewandte Chemie international edition. Volume 58:Issue 48(2019)
• Page Start: 17365
• Page End: 17374
• Publication Date: 2019-10-17
• Subjects: 18-electron rule -- alkaline earth metals -- benzene complexes -- bonding analysis -- matrix isolation spectroscopy; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201908572
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: We report the synthesis and spectroscopic identification of the trisbenzene complexes of strontium and barium M(Bz)3 (M=Sr, Ba) in low‐temperature Ne matrix. Both complexes are characterized by a D 3 symmetric structure involving three equivalent η 6 ‐bound benzene ligands and a closed‐shell singlet electronic ground state. The analysis of the electronic structure shows that the complexes exhibit metal–ligand bonds that are typical for transition metal compounds. The chemical bonds can be explained in terms of weak donation from the π MOs of benzene ligands into the vacant (n−1)d AOs of M and strong backdonation from the occupied (n−1)d AO of M into vacant π* MOs of benzene ligands. The metals in these 20‐electron complexes have 18 effective valence electrons, and, thus, fulfill the 18‐electron rule if only the metal–ligand bonding electrons are counted. The results suggest that the heavier alkaline earth atoms exhibit the full bonding scenario of transition metals. Abstract : Bonding scenarios : The synthesis and spectroscopic identification of the trisbenzene complexes of strontium and barium M(Bz)3 (M=Sr, Ba) in a low‐temperature Ne matrix is reported. The complexes exhibit metal–ligand bonds that are typical for transition‐metal compounds. The results suggest that the heavier alkaline‐earth atoms exhibit the full bonding scenario of transition metals.