102853-22-5Relevant academic research and scientific papers
Copper-catalyzed oxidative dehydrogenative functionalization of alkanes to allylic esters
Mondal, Rakesh,Chakraborty, Gargi,van Vliet, Kaj M.,van Leest, Nicolaas P.,de Bruin, Bas,Paul, Nanda D.
supporting information, (2019/11/11)
Herein, we report a general, efficient and solvent-free method for the one-pot synthesis of allylic esters via dehydrogenation of unactivated alkanes and subsequent oxidative cross coupling with different substituted carboxylic acids. A simple, well defined and air stable Cu(II)-complex, [Cu(MeTAA)], featuring a tetraaza-macrocyclic ligand (tetramethyltetraaza[14]annulene (MeTAA)) is used as the catalyst. A wide variety of substituted allylic esters were synthesized in high yields starting from readily available starting materials. Control reactions were carried out to understand the reaction sequence and the plausible mechanism.
Iron-catalyzed esterification of allylic sp3 C–H bonds with carboxylic acids: Facile access to allylic esters
Lu, Bing,Zhu, Fan,Wang, Dan,Sun, Hongmei,Shen, Qi
supporting information, p. 2490 - 2494 (2017/05/31)
The first general and efficient iron-catalyzed esterification of allylic sp3 C–H bonds with carboxylic acids using ionic iron(III) complexes (1–4) as a catalyst and DTBP (DTBP?=?di-tert-butyl peroxide) as an oxidant is achieved. A variety of allylic esters were synthesized in good to excellent yields using the ionic iron(III) complex 2 as a catalyst in a 5?mol% loading. This reaction is characterized by its high efficiency, broad substrate scope with excellent steric hindrance tolerance and good functional group compatibility.
Copper-catalyzed oxidative dehydrogenative carboxylation of unactivated alkanes to allylic esters via alkenes
Tran, Ba L.,Driess, Matthias,Hartwig, John F.
supporting information, p. 17292 - 17301 (2015/02/02)
We report copper-catalyzed oxidative dehydrogenative carboxylation (ODC) of unactivated alkanes with various substituted benzoic acids to produce the corresponding allylic esters. Spectroscopic studies (EPR, UV-vis) revealed that the resting state of the catalyst is [(BPI)Cu(O2CPh)] (1-O2CPh), formed from [(BPI)Cu(PPh3)2], oxidant, and benzoic acid. Catalytic and stoichiometric reactions of 1-O2CPh with alkyl radicals and radical probes imply that C-H bond cleavage occurs by a tert-butoxy radical. In addition, the deuterium kinetic isotope effect from reactions of cyclohexane and d12-cyclohexane in separate vessels showed that the turnover-limiting step for the ODC of cyclohexane is C-H bond cleavage. To understand the origin of the difference in products formed from copper-catalyzed amidation and copper-catalyzed ODC, reactions of an alkyl radical with a series of copper-carboxylate, copper-amidate, and copper-imidate complexes were performed. The results of competition experiments revealed that the relative rate of reaction of alkyl radicals with the copper complexes follows the trend Cu(II)-amidate > Cu(II)-imidate > Cu(II)-benzoate. Consistent with this trend, Cu(II)-amidates and Cu(II)-benzoates containing more electron-rich aryl groups on the benzamidate and benzoate react faster with the alkyl radical than do those with more electron-poor aryl groups on these ligands to produce the corresponding products. These data on the ODC of cyclohexane led to preliminary investigation of copper-catalyzed oxidative dehydrogenative amination of cyclohexane to generate a mixture of N-alkyl and N-allylic products.
Alkylation of Allylic Derivatives. 11. Copper(I)-Catalyzed Cross Coupling of Allylic Carboxylates with Grignard Reagents
Tseng, Chung Chyi,Paisley, Steven D.,Goering, Harlan L.
, p. 2884 - 2891 (2007/10/02)
Reactions of allylic carboxylates with Grignard reagents containing catalytic amounts (1-10 mol percent) of cuprous salts give high yields of cross-coupled products.With alkyl Grignard reagents, regiochemistry can be controlled by choice of cuprous salt.With cuprous halides, little regiospecificity is observed.There is a small excess of γ-coupling in unbiased systems such as 5-methyl-2-cyclohexenyl (1), 2-cyclohexenyl (3), and β-phenylallyl (5) carboxylates.With CuCN, complete regiospecificity (exclusive γ-coupling) is observed with all alkyl Grignard reagents in unbiased systems, and with n-butylmagnesium halide >97percent γ-coupling results with α-methyl-γ-phenylallyl pivalate (7-OPiv) which is biased in favour of coupling at the α-position.In sharp contrast to alkyl Grignard reagents, phenyl and vinyl Grignard reagents containing CuCN show no regiospecificity.
