Synthesis, Cycloaddition, and Cycloreversion Reactions of Mononuclear Titanocene-oxo Complexes was written by Nguyen, Trang T.;Kortman, Gregory D.;Hull, Kami L.. And the article was included in Organometallics in 2016.SDS of cas: 3718-65-8 This article mentions the following:
Titanocene-oxo complexes of the type Cpx2Ti=O(L) (Cpx = pentamethylcyclopentadienyl; tetramethylcyclopentadienyl; L = pyridine or derivatives) are synthesized from the corresponding titanocene-ethylene complexes via oxidation with pyridine N-oxides or styrene oxide. These oxo complexes react with alkynes, nitriles, and α,β-unsaturated carbonyls to form titanacycles, which undergo exchange reactions with organic substrates or react with 4-dimethylaminopyridine to regenerate the titanocene-oxo. Mechanistic experiments support a dissociative mechanism in which the first step is rate-determining retrocycloaddn. followed by trapping of the reactive [Cpx2Ti=O] species. In the case of the retro-[4+2]-cycloaddition from dioxatitanacyclohexene complexes, a Hammett study gives ρ values of -1.18 and -1.04 for substituents on two different Ph rings on the metallacycles, suggesting pos. charge buildup and a slightly asynchronous cycloreversion in the rate-determining step. In the experiment, the researchers used many compounds, for example, 3,5-Dimethylpyridine 1-oxide (cas: 3718-65-8SDS of cas: 3718-65-8).
3,5-Dimethylpyridine 1-oxide (cas: 3718-65-8) belongs to pyridine derivatives. In contrast to benzene, Pyridine’s electron density is not evenly distributed over the ring, reflecting the negative inductive effect of the nitrogen atom. Pyridine, its benzo and pyridine-based compounds play diverse roles in organic chemistry. Pyridine-based materials are valued for their optical and physical properties as well as their medical potential. SDS of cas: 3718-65-8