126135-10-2

Upstream product

• 163400-78-0 2,2-Dimesitylethenyl acetate 
• 54288-04-9 2,2-dimesityl-vinyl alcohol 

Relevant academic research and scientific papers

Probing M-O bond cleavage in silicon and titanium bisenolate radical cations

In this study, several novel sterically congested silicon and titanium bisenolates of exceptional hydrolytic stability have been synthesized and characterized. The structure of the titanium bisenolate T2 could be determined by X-ray structure analysis. Pr

Zirconium enolate radical cations in solution - Characterisation and kinetics of their mesolytic Zr-O bond cleavage

Six zirconocene enolate radical cations and one hydroquinone biszirconocene radical cation have been generated and characterised in solution by standard and fast scan cyclic voltammetry. The electroanalytical results along with those from product analysis of preparative one-electron oxidations indicate that the sterically congested radical cations undergo a mesolytic Zr-O bond cleavage process. The kinetics of the mesolytic Zr-O bond cleavage yielding zirconocene cations and the lifetime (t1/2) of the zirconium enolate radical cations in dichloromethane at room temperature are determined.

Enol radical cations in solution. Part 12. Synthesis and electrochemical investigations of a stable enol linked to a ferrocene redox centre

The synthesis of the first stable enol linked to a ferrocene redox centre is reported. After one-electron oxidation of this compound we receive a persistent radical cation that can be activated by a second one-electron oxidation step. The resulting enol dication undergoes rapid deprotonation to a diradical cation which finally furnishes two benzofurans as products. The mechanism of this reaction and the role of the ferrocene as a redox relay is discussed.

First characterisation of zirconium enolate radical cations in solution and their mesolytic bond cleavage to zirconocene cations

Zirconocene enolate radical cations are generated and characterised in solution for the first time; the sterically congested radical cations undergo a mesolytic Zr-O bond cleavage process yielding zirconocene cations, the kinetics of which are determined.

Titanium enolate radical cations in solution: generation, characterization, and their reactions

For the first time, titanium enolate radical cations were characterized in cyclic voltammetry experiments. Preparative one-electron oxidation of titanium enolates 1-3 led to the formation of benzofurans B1-B3 through mesolytic Ti-O bond fragmentation to α-carbonyl radical and a cationic titanocene(IV) species. With 1+, the kinetics of the Ti-O bond cleavage was investigated by fast scan cyclic voltammetry providing a first-order rate constant kf = 850 ± 50 s-1 in acetonitrile at room temperature. The titanium enolate radical cations 1+, 3+, 4+ and 5+ were characterized by EPR spectroscopy, qualifying these species as electrophilic radicals. This feature can be exploited in C-C bond formation reactions such as the formal dimerization of 6 to 2,3-dimethyl1,4-diphenylbuta-1,4-dione D6, which takes place on stage of the radical cation 6+. VCH Verlagsgesellschaft mbH.

Erste Charakterisierung eines Titanenolat-Radikalkations in Loesung - C-C-Bindungsknuepfung und Kinetik der mesolytischen Ti-O-Bindungsspaltung

Keywords: Cyclovoltammetrie; Elektronentransfer; Radikalionen; Titanenolate

Mesolytic Cleavage of the O-CO-Bond in Enol Acetate Cation Radicals with Direct Formation of α-Carbonyl Cations. Mechanistic and Synthetic Aspects

For the first time, enol ester cation radicals are reversibly monitored in a cyclic voltammetry experiment.Preparative one-electron oxidation of enol acetates A1-A4 leads to the formation of benzofurans B1-B4 through mesolytic O-CO bond fragmentation to α-carbonyl cations and the acetyl radical.With A3(.+), the kinetics of the O-CO bond cleavage was investigated by cyclic voltammetry, providing ΔH(excit.) = 17.0 kcal mol-1 and ΔS(excit.) = 11 cal mol-1 K-1 in dichloromethane.The slioghtly increased rate of bond dissociation upon adition of acetonitrile is explained with charge localization in the transition state rather than with a solvent-assisted bond cleavage mechanism.The occurrence of curve crossing and isopotential points in the cyclic voltammograms of the model compounds a1-A4 at low scan rates can be rationalized by a multiparameter reaction scheme based on an ECCEDISP mechanism, digital simulation of which confirmed the cleavage selectivety and allowed for the determination of the involved rate constants of the homogeneous chemical reaction steps.

Enol Cation Radicals in Solution. 4. An Improved Synthesis of 4,6,7-Trimethylbenzofurans by Oxidation of β-Mesityl Substituted Enols

An improved synthetic access for the construction of 4,6,7-trimethylbenzofurans (B1-B8) through the one-electron oxidation of mesityl-substituted enols (E1-E8) is presented.The transformation can be accomplished in good to excellent yields by using variou

Controlled Oxidation of Enolates to α-Carbonyl Radicals and α-Carbonyl Cations

Depending on the oxidation strength of the one-electron oxidants either persistent α-carbonyl radicals or α-carbonyl cation derived benzofurans are formed from enolates A1-A6, a result which can readily be rationalized by the measured oxidation potentials