4409-85-2Relevant academic research and scientific papers
Aqueous Oxidations Started by TiO2 Photoinduced Holes Can Be a Rate-Determining Step
Gong, Yuanzheng,Yang, Chun,Ji, Hongwei,Chen, Chuncheng,Ma, Wanhong,Zhao, Jincai
supporting information, p. 2048 - 2051 (2017/08/23)
In aqueous TiO2 photocatalytic hydroxylation of weakly polar aromatics, a series of inverse H/D KIEs of 0.7–0.8 were observed, which is different than the normal H/D kinetic isotope effects (KIEs) usually observed for polar aromatics. This result indicated that the oxidation started by photo-induced hvb + can be the rate-determining step.
Metal-Free sp2-C-H Borylation as a Common Reactivity Pattern of Frustrated 2-Aminophenylboranes
Chernichenko, Konstantin,Lindqvist, Markus,Kótai, Bianka,Nieger, Martin,Sorochkina, Kristina,Pápai, Imre,Repo, Timo
supporting information, p. 4860 - 4868 (2016/05/10)
C-H borylation is a powerful and atom-efficient method for converting affordable and abundant chemicals into versatile organic reagents used in the production of fine chemicals and functional materials. Herein we report a facile C-H borylation of aromatic and olefinic C-H bonds with 2-aminophenylboranes. Computational and experimental studies reveal that the metal-free C-H insertion proceeds via a frustrated Lewis pair mechanism involving heterolytic splitting of the C-H bond by cooperative action of the amine and boryl groups. The adapted geometry of the reactive B and N centers results in an unprecedentently low kinetic barrier for both insertion into the sp2-C-H bond and intramolecular protonation of the sp2-C-B bond in 2-ammoniophenyl(aryl)- or -(alkenyl)borates. This common reactivity pattern serves as a platform for various catalytic reactions such as C-H borylation and hydrogenation of alkynes. In particular, we demonstrate that simple 2-aminopyridinium salts efficiently catalyze the C-H borylation of hetarenes with catecholborane. This reaction is presumably mediated by a borenium species isoelectronic to 2-aminophenylboranes.
Structural dependence of isotope effects in 1H and 13C nuclear magnetic resonance spectra of the trans-N-benzylideneaniline imino group
Novak, Predrag,Meic, Zlatko,Vikic-Topic, Drazen,Smrecki, Vilko,Plavec, Janez
, p. 327 - 333 (2007/10/03)
Deutrium- and 15N-induced isotope effects on 1H and 13C chemical shifts of the imino moiety of 16 trans-N-benzylideneaniline (tBA) isotopomers were determined and analysed. These effects appear to be a sensitive probe of m
Mechanistic aspects of the reaction of anionic iron(0)-olefin complexes with organic halides. detection and characterization of paramagnetic organometallic intermediates
Hill, Dale H.,Parvez, Masood A.,Sen, Ayusman
, p. 2889 - 2901 (2007/10/02)
The scope and the mechanism of the reactions of [CpFe(COD)][Li(TMEDA) (Cp = C5H5-; COD = 1,5-cyclooctadiene; TMEDA = Me2NCH2CH2NMe2), 1, with a number of organic monohalides and geminal dih
1,2,4,6-CYCLOHEPTATETRAENE: THE KEY INTERMEDIATE IN ARYLCARBENE INTERCONVERSIONS AND RELATED C7H6 REARRANGEMENTS
McMahon, Robert J.,Abelt, Christopher J.,Chapman, Orville L.,Johnson, Jeffery W.,Kreil, Curits L.,et al.
, p. 2456 - 2469 (2007/10/02)
Thermolysis or photolysis of phenyldiazomethane (2) produces phenylmethylene (3), which ring-expands to give 1,2,4,6-cycloheptatetraene (6).Spectroscopic and chemical evidence rule out bicyclo(4.1.0)hepta-2,4,6-triene (4), cycloheptatrienylidene (5), and bicyclo(3.2.0)hepta-1,3,6-triene (11) intermediates.The strained allene in cycloheptatetraene (6) exhibits infrared absorption at 1824 and 1816 cm-1.Deuterium substitution produces the expected 10-cm-1 shift in the allene absorption.Fluorine or chlorine substitution substantially enhances the allene absorption intensity.Deuterium labeling studies reveal that the intramolecular chemistry of cycloheptatetraene (6) involves reversible thermal or photochemical equilibriation with phenylmethylene (3).The intermolecular chemistry of 6 involves dimerization.At temperatures as low as 10 K, 6 forms a labile (2+2) dimer,7, which undergoes thermally allowed, electrocyclic ring opening to give heptafulvalene (8) upon warming to room temperature.The rearrangements of 7-acetoxynorbornadiene (9), 2-diazobicyclo(3.2.0)hepta-3,6-diene (31), and 8-diazobicyclo(2.2.2)octa-2,5-dien-7-one (33) all involve cycloheptatetraene (6) intermediates.
INTRAMOLECULAR DEUTERIUM ISOTOPE EFFECTS IN THE META PHOTOCYCLOADDITION OF AROMATIC COMPOUNDS TO ALKENES.
Vaal, P. de,Lodder, G.,Cornelisse, J.
, p. 4585 - 4590 (2007/10/02)
The effect of substitution of hydrogen by deuterium in some aromatic compounds on product distributions in the meta photocycloaddition to alkenes was investigated.The isotope effects found are in agreement with a polar mechanism.
An Increment System for Deuterium Isotope Effects on 13C Chemical Shifts of Methylated Benzenes
Berger, Stefan,Diehl, Bernd W. K.
, p. 1073 - 1076 (2007/10/02)
The complete series of all possible benzenes bearing one deuterium atom and one to five methyl groups was synthesized.The deuterium isotope effects on the carbon chemical shifts of the aromatic and aliphatic carbon atoms were measured and shown to obey an empirical increment system.The isotope effects over one bond correlate with the C,H spin coupling constants. KEY WORDS 13C NMR, deuterium isotope effects, methylbenzenes
Unusual Deuterium Isotope Effects in 13C NMR Spectra of trans-Stilbene
Meic, Zlatko,Vikic-Topic, Drazen,Gusten, Hans
, p. 237 - 244 (2007/10/02)
A detailed analysis of the 13C NMR spectra of trans-stilbene and ten deuteriated trans-stilbenes has been undertaken.Some unusual deuterium isotope effects on carbon-hydrogen spin-spin coupling constants could not be explained by the ordinary primary and
