Separation of Five Linearly Aligned Carbons into Two-Carbon and Three-Carbon Groups on Titanium

Vivid Wording for the Chemistry of Group 4 Metallocene Complexes

Three selected examples for the use of unusual wording to describe the organometallic chemistry of Group 4 metallocenes are explained and discussed. The term "tuck(ed)-in" concerns the behavior of decamethyltitanocene [(C₅ Me₅ )₂ Ti] and similar complexes in which one or two methyl groups form the titanium hydride complex [(C₅ Me₅ )(C₅ Me₄ CH₂ )TiH] or other hydride complexes by C-H activation. In the so-called "merry-go-round reaction" the rearrangement of C atoms bound to titanium in organometallic molecules is described which corresponds to the rotation of two C atoms along with a rotation of the six-membered ring in a dihydroindenyl moiety at titanium. In the third example "migration" or "tobogganing" concerns the "sliding" of titanocene along the chain of a linear polyyne by coordination to one or more triple bonds. In all these reactions changes of the coordination mode of the metal at Cp or substrate ligands by intramolecular dynamics occur.

Formation of a spiro compound via coupling of a cyclopentadienyl ligand with a diene moiety of titanacyclopentadiene

The treatment of titanacyclopentadienes with bismuth(iii) chloride gave spiro compounds in moderate yields. Two carbon atoms of the diene moiety of the titanacyclopentadiene were connected to one carbon atom of the Cp ligand. This is in sharp contrast to the formation of dihydroindene derivatives, where two carbon-carbon bonds were formed between the diene moiety and the adjacent two carbon atoms of the Cp ligand.

Metal-Involving Synthesis and Reactions of Oximes

This review classifies and summarizes the past 10-15 years of advancements in the field of metal-involving (i.e., metal-mediated and metal-catalyzed) reactions of oximes. These reactions are diverse in nature and have been employed for syntheses of oxime-based metal complexes and cage-compounds, oxime functionalizations, and the preparation of new classes of organic species, in particular, a wide variety of heterocyclic systems spanning small 3-membered ring systems to macroheterocycles. This consideration gives a general outlook of reaction routes, mechanisms, and driving forces and underlines the potential of metal-involving conversions of oxime species for application in various fields of chemistry and draws attention to the emerging putative targets.