Direct Synthesis of Pentaarylcyclopentadienyl Sandwich and Half-Sandwich Complexes of s‑, p‑, and d‑Block Metals

• Published in: Organometallics 2020-01, Vol.39 (1), p.206-216
• Main Authors: Schulte, Yannick, Weinert, Hanns, Wölper, Christoph, Schulz, Stephan
• Format: Article
• Language: English
• ISSN: 0276-7333; 1520-6041
• DOI: 10.1021/acs.organomet.9b00741

The sterically demanding pentaarylcyclopentadienyl radical CpBIGt‑Bu• (1; CpBIGt‑Bu = Cp­(4-t-Bu-Ph)5) reacts with group 2, group 13, and group 14 metal amalgams to form the following complexes of the type CpBIGt-Bu 2M (M = Ca (3), Sr (4), Ba (5)), CpBIGt‑BuM′ (M′ = Ga (6), In (7), Tl (8)) and CpBIGt-Bu 2M′′ (M′′ = Sn (10), Pb (11)). In addition, metallocenes CpBIG 2Mg (2), CpBIG 2Hg (12), and CpBIG 2Ge (9) were formed in reactions of 1 with magnesium anthracene (2) and elemental mercury (12) as well as by salt metathesis between CpBIGt‑BuK and GeCl2·dioxane (9). 6 was found to react with (coe)­Cr­(CO)5 (coe = cis-cyclooctene) with formation of CpBIGt‑BuGaCr­(CO)5 (13). 2–13 were characterized by elemental analysis and IR and NMR spectroscopy. In addition, the solid-state structures of 2, 4, 5, and 9–13 were determined by single-crystal X-ray diffraction.