Rhenium-Catalyzed Oxidative Cyanation of Tertiary Amines with TMSCN

2013 ◽  
Vol 2013 (32) ◽  
pp. 7286-7290 ◽  
Author(s):  
Aijun Lin ◽  
Hao Peng ◽  
Ablimit Abdukader ◽  
Chengjian Zhu
Keyword(s):  
2019 ◽  
Author(s):  
Christopher J. Legacy ◽  
Frederick T. Greenaway ◽  
Marion Emmert

We report detailed mechanistic investigations of an iron-based catalyst system, which allows the α-C-H oxidation of a wide variety of amines, including acyclic tertiary aliphatic amines, to afford dealkylated or amide products. In contrast to other catalysts that affect α-C-H oxidations of tertiary amines, the system under investigation employs exclusively peroxy esters as oxidants. More common oxidants (e.g. tBuOOH) previously reported to affect amine oxidations via free radical pathways do not provide amine α-C-H oxidation products in combination with the herein described catalyst system. Motivated by this difference in reactivity to more common free radical systems, the investigations described herein employ initial rate kinetics, kinetic profiling, Eyring studies, kinetic isotope effect studies, Hammett studies, ligand coordination studies, and EPR studies to shed light on the Fe catalyst system. The obtained data suggest that the catalytic mechanism proceeds through C-H abstraction at a coordinated substrate molecule. This rate-determining step occurs either at an Fe(IV) oxo pathway or a 2-electron pathway at a Fe(II) intermediate with bound oxidant. We further show via kinetic profiling and EPR studies that catalyst activation follows a radical pathway, which is initiated by hydrolysis of PhCO3 tBu to tBuOOH in the reaction mixture. Overall, the obtained mechanistic data support a non-classical, Fe catalyzed pathway that requires substrate binding, thus inducing selectivity for α-C-H functionalization.<br>


2013 ◽  
Vol 33 (4) ◽  
pp. 717-722 ◽  
Author(s):  
Wei HE ◽  
Songbo HE ◽  
Chenglin SUN ◽  
Kaikai WU ◽  
Liandi WANG ◽  
...  
Keyword(s):  

2012 ◽  
Vol 8 (6) ◽  
pp. 1146-1154
Author(s):  
Rose M. McConnell ◽  
Kalyani Inapudi ◽  
Naveen Kadasala ◽  
Karthika Yarlagadda ◽  
Priya Velusamy ◽  
...  
Keyword(s):  

1987 ◽  
Vol 52 (11) ◽  
pp. 2699-2709 ◽  
Author(s):  
Dalimil Dvořák ◽  
Zdeněk Arnold

Reaction of arylmethylenemalonaldehydes with tributylphosphine and tertiary amines affords compounds of dipolar structure whereas reaction with primary and secondary amines leads to 1,4-addition products. Salts of nucleophilic inorganic anions add to arylmethylenemalonaldehydes under formation of salts of substituted malonaldehydes.


1980 ◽  
Vol 45 (2) ◽  
pp. 406-414 ◽  
Author(s):  
Jiří Svoboda ◽  
Oldřich Paleta ◽  
Václav Dědek

Dimerisation of trifluoropropenenitrile (I) in the presence of potassium fluoride and tertiary amines afforded a mixture of stereoisomeric perfluoro-4-methyl-pentenedinitriles (II), higher-boiling compounds, and 2,3,3,3-tetrafluoropropanenitrile (III) which arises by proton transfer from the solvent molecule. Under optimum conditions, product II was obtained in about 50% yield. Reaction of the nitrile I with methyl trifluoropropenoate (IV) gave, besides the dimers II and V, the product of addition of the nitrile I to the propenoate, IV, i.e. methyl 4-cyanoperfluoro-2-pentenoate (VI), and the addition product of the propenoate IV to the nitrile I, i.e. methyl 4-cyanoperfluoro-2-methyl-3-butenoate (VII). The relative reactivity if I and IV is discussed. The ratio of stereoisomers in II, V, VI and VII indicates that the magnitude of the steric substituent effect, operating in the reaction mechanism, decreases in the order -CFCF3.(COOCH3) > -CFCF3(CN) > -COOCH3 > -CN.


2021 ◽  
pp. 120443
Author(s):  
Alma Berenice Jasso-Salcedo ◽  
Xia Wang ◽  
Zoltán Bacsik ◽  
Niklas Hedin
Keyword(s):  

Polymers ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 1944
Author(s):  
Alma Antonia Pérez-Mondragón ◽  
Carlos Enrique Cuevas-Suárez ◽  
Jesús García-Serrano ◽  
Nayely Trejo-Carbajal ◽  
A. Lobo-Guerrero ◽  
...  

This work reports the use of two monomers with two tertiary amines and four methacrylic (TTME) or acrylic (TTAC) terminal groups as co-initiators in the formulation of experimental resin adhesive systems. Both monomers were characterized by FT-IR and 1H NMR spectroscopies. The control adhesive was formulated with BisGMA, TEGDMA, HEMA, and the binary system CQ-EDAB as a photo-initiator system. For the experimental adhesives, the EDAB was completely replaced for the TTME or the TTAC monomers. The adhesives formulated with TTME or TTAC monomers achieved double bond conversion values close to 75%. Regarding the polymerization rate, materials formulated with TTME or TTAC achieved lower values than the material formulated with EDAB, giving them high shelf-life stability. The degree of conversion after shelf simulation was only reduced for the EDAB material. Ultimate tensile strength, translucency parameter, and micro-tensile bond strength to dentin were similar for control and experimental adhesive resins. Due to their characteristics, TTME and TTAC monomers are potentially useful in the formulation of photopolymerizable resins for dental use with high shelf-life stability.


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