title: Bismuth-lithium bonding in the ion pairs: LiBiL2, where L = a porphyrin or a salen ligand.
abstract: From the reaction between BiCl3 (1 equiv.) and LiN(SiMe3)2 (4 equiv.) and LH2 (2 equiv.), where L = a tetraphenylporphyrin, TPP, an octaethylporphyrin, OEP and phsalen in THF the title compounds have been obtained LiBiTPP2, LiBiOEP2, and LiBi(phsalen)2 and LiBi(phsalen)2·THF. Crystals grown from CH2Cl2-hexanes are colored; (green), (red-purple) and and (red-orange). The molecular structures of compound , and were determined by single-crystal X-ray crystallography and are shown to have short LiBi bonds of distance 2.8 Å involving the LiL(-)BiL(+). Compound shows a slipped structure involving Li to two oxygens and a LiBi distance of 3.1 Å. Compounds and undergo a rapid reversible exchange in toluene-d8 at 90 °C. The MALDI-MS yields weak molecular ions due to LiBiL2(+/-) with more intense ions due to BiL(+) and LiL(-) in the positive and negative modes. The short Li(+) to Bi(3+) distances are comparable to those seen in LiBi compounds, such a LiBiR2, and are comparable to those seen by Pyykkö (P. Pyykkö, J. Phys. Chem. A, 2015, 119, 2326; P. Pyykkö and M. Atsumi, Chem. - Eur. J., 2009, 15, 186; P. Pyykkö and M. Atsumi, Chem. - Eur. J., 2009, 15, 12770) for Li-Bi bonds. These can be seen to be involving Bi6s6p hybrid lone-pairs to Li(+) atoms. The lithium bis(bistrimethylsilyl)amide (2 equiv.) and phsalenH2 in THF gave a compound having Li2L·2THF, . Crystallographically compound contains two Li(+) atoms, one coordinated to five atoms LiO2N2·THF. and the other being coordinated to three atoms, LiO2·THF. By (7)Li and (1)H NMR both lithium atoms share an equivalent environment.
authors.affiliation: Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, USA. Chisholm@chemistry.ohio-state.edu.
authors.forename: Vagulejan
authors.initials: V
authors.lastname: Balasanthiran
authors.forename: Malcolm H
authors.initials: MH
authors.lastname: Chisholm
authors.forename: Christopher B
authors.initials: CB
authors.lastname: Durr