applications of the Tebbe reagent (108) in a metathesis-based ..

The Petasis reagent is an organotitanium compound with the formula CpTi(CH)

Kauffmann olefination - Wikipedia

Ti-1 is especially useful for effecting RCM by the carbonyl–olefination reaction, while the RCM of enynes, catalyzed by Ru-2, is another valuable metathesis reaction.">

In terms of reactivity, it resembles the Tebbe reagent and Wittig reaction .

Tebbe Reagent 67719-69-1 | TCI Chemicals (India) Pvt. Ltd.

Olefin Metathesis in Cyclic Ether Formation. Direct Conversion of Olefinic Esters to Cyclic Enol Ethers with Tebbe-Type Reagents K. C. Nicolaou,* Maarten H. D. Postema, and

Petasis Reagent The PETASIS REAGENT is an organotitanium compound with the formula Cp2Ti(CH3)2.

Masking its potential via Lewis acid stabilization, Tebbe tamed the titanium methylidene moiety, leading many other scientists to exploit the wide-ranging reactivity of such a unit, including olefin metathesis, methylenation, and metallacyclobutane formation, among others.

The Kauffmann olefination is a chemical reaction to convert aldehydes ..


Features And Essays 2010 | P H O T O ..

The Tebbe reagent is the organometallic compound with the formula (C5H5)2TiCH2ClAl(CH3)2. It used in the methylenation of carbonyl compounds, that is it converts organic compounds containing the R2C=O group into the related R2C=CH2 derivative. It is a red solid that is pyrophoric in the air, and thus is typically handled with air-free techniques. It was originally synthesized by Fred Tebbe at DuPont Central Research.

olefin metathesis | Chem-Station Int. Ed.

CAR B E N E COMPLEXES Our first approach to the development of olefination reagents was based on observations originally made for the "Tebbe" reagent that low-valent titanium methylene complexes could methylenate a wide variety of organic carbonyls under mild conditions'.

Olefin Metathesis - Chemistry LibreTexts

Original Commentary Daniel A. Straus San JoseState University, CA, USA Tebbe Reagent asa Source of'Cp 2 2 2 Ti=CH 2 2 2 '. The com-plexCp 2 TiCH 2 ·AlMe 2 Cl, commonly referred to as the Tebbe reagent,. 5 isasourceofthe reactive titanium methylene species 'Cp 2 Ti=CH 2 'asshownineq 1.

Olefin Metathesis: The Nobel Prize in ..

The Tebbe reagent has been renowned for decades for its utility as a methylene-transfer reagent. Although DuPont chemist Frederick N. Tebbe first isolated the titanocene-aluminum complex in 1974, it has eluded definitive structural characterization because of its high reactivity, chemists believe. Researchers at Indiana University led by Rick Thompson and , both now at the University of Pennsylvania, have solved the structure of the Tebbe reagent cocrystallized with an inert impurity ( 2013, DOI: ). The project began when Thompson was a graduate teaching assistant for an advanced undergraduate inorganic chemistry lab in which the students had to prepare and use the Tebbe reagent. Thompson noticed indications of an impurity and pursued an analysis that culminated in the crystal structure, Mindiola says. The geometry of the reagent complex is largely as Tebbe predicted and studies of other compounds had indicated, with a (C5H5)2Ti group bridged to an Al(CH3)2 fragment through Cl and CH2 groups. In the impurity, the bridging CH2 is replaced by a second Cl. What surprised Mindiola and colleagues was the impurity, which makes up 40 to 50% of their crystallized reagent samples and had gone unrecognized in the past, even though Tebbe had predicted it.

Olefin Metathesis, Grubbs Reaction - Organic chemistry

The first practical metathesis system was introduced in 1978 by Tebbe based on the (what later became known as the) . In a model reaction isoptopically labeled carbon atoms in and switched places: