38574-14-0

Usage

Type

Deuterated form of 1,3,5-trimethylbenzene

Physical State

Colorless liquid

Common Uses

a. Solvent
b. Production of dyes
c. Production of pharmaceuticals

Deuterium Content

Contains three deuterium atoms in place of three hydrogen atoms

Application in NMR Spectroscopy

a. Produces distinct signals in NMR spectra
b. Helps identify and analyze the structure of organic molecules

Additional Uses

a. Tracer in environmental studies
b. Tracer in geochemical studies

Upstream product

• 108-67-8 1,3,5-trimethyl-benzene 
• 4028-63-1 iodomesitylene 
• 1603-55-0 cyclohexene-d10 
• 185416-14-2 4-(1-butyl)phenylmagnesium bromide 

Downstream Products

• 75918-88-6 C₂₄H₂₀⁽²⁾H₃N₃ 

Relevant academic research and scientific papers

Mechanism of electrophilic fluorination of aromatic compounds with NF-reagents

Kinetic isotope effects H/D in electrophilic fluorination of aromatic compounds with NF-reagents were investigated. The small values of k H/k D (0.86-1.00) are in agreement with the polar reaction mechanism where the Wheland complex

Catalytic deuteration of C(sp2)-H bonds of substituted (Hetero)arenes in a Pt(II) CNN-pincer complex/2,2,2Trifluoroethanol-d1 system: Effect of substituents on the reaction rate and selectivity

Thirty four (hetero)arene derivatives have been tested in catalytic H/D exchange reactions involving their C(sp2)- H bonds and 2,2,2-trifluoroethanol-d1 (TFE-d1) in the presence of the homogeneous Pt(II) complex 1 supported by a sulfonated CNN-pincer ligand at 80 °C. The 18 substrates, including one pharmaceutical (naproxen), that are stable in the presence of 1 and are active in the H/D exchange reaction have been characterized by their position-specific extent of deuteration and, in a number of cases, the reaction kinetic selectivity. For the most reactive substrates the extent of deuteration approaches the expected statistical distribution of the exchangeable H and D atoms: e.g., 67-69% for phenol after 23 h and 88% for indole β-CH bonds after 45 min. For a few substrates (N,N-dimethylaniline, indole, nitrobenzene) the H/D exchange is highly position selective. No satisfactory correlation was found between the position-specific (meta, para) H/D exchange rate constants for X-monosubstituted benzenes and Hammett σX constants. This observation was proposed to be related to the concerted nature of the CH bond activation, the rate-determining CH bond oxidative addition at a Pt(II) center. A novel scale of Hammett σMX constants was introduced to characterize the reactivity of C(sp2)-H bonds in transition-metal-mediated reactions. The experimentally determined position-specific Gibbs energies of activation of the H/D exchange in substituted benzenes (meta and para positions) as well as in thiophene (α and β positions) were matched satisfactorily using DFT calculations.

Iron-catalyzed allylic arylation of olefins via C(sp3)-H activation under mild conditions

An aryl Grignard reagent in the presence of mesityl iodide converts an allylic C-H bond of a cycloalkene or an allylbenzene derivative into a C-C bond in the presence of a catalytic amount of Fe(acac)3 and a diphosphine ligand at 0 C. The stereo- and regioselectivity of the reaction, together with deuterium labeling experiments, suggest that C-H bond activation is the slow step in the catalytic cycle preceding the formation of an allyliron intermediate.

N-doping of organic electronic materials using air-stable organometallics: A mechanistic study of reduction by dimeric sandwich compounds

Several 19-electron sandwich compounds are known to exist as "2×18-electron" dimers. Recently it has been shown that, despite their air stability in the solid state, some of these dimers act as powerful reductants when co-deposited from either the gas phase or from solution and that this behavior can be useful in n-doping materials for organic electronics, including compounds with moderate electron affinities, such as 6,13-bis[tri(isopropyl)silylethynyl]pentacene (3). This paper addresses the mechanisms by which the dimers of 1,2,3,4,5-pentamethylrhodocene (1 b 2), (pentamethylcyclopentadienyl)(1,3,5-trialkylbenzene)ruthenium (alkyl=Me, 2 a2; alkyl=Et, 2 b2), and (pentamethylcyclopentadienyl)(benzene)iron (2 c2) react with 3 in solution. Vis/NIR and NMR spectroscopy, and X-ray crystallography indicate that the products of these solution reactions are 3.- salts of the monomeric sandwich cations. Vis/NIR kinetic studies for the Group 8 dimers are consistent with a mechanism whereby an endergonic electron transfer from the dimer to 3 is followed by rapid cleavage of the dimer cation. NMR crossover experiments with partially deuterated derivatives suggest that the C-C bond in the 1 b2 dimer is much more readily broken than that in 2 a 2; consistent with this observation, Vis/NIR kinetic measurements suggest that the solution reduction of 3 by 1 b2 can occur by both the mechanism established for the Group 8 species and by a mechanism in which an endergonic dissociation of the dimer is followed by rapid electron transfer from monomeric 1 b to 3. Doped up: Air-stable dimers of pentamethylrhodocene and pentamethylcyclopentadienyl arene ruthenium and iron can be used to n-dope acceptors such as bis[tri(isopropyl)silylethynyl] pentacene. NMR crossover experiments and variable-temperature Vis/NIR kinetic measurements indicate that, depending on the reaction conditions and the choice of dimer and acceptor, this doping can take place by two different mechanisms (see scheme). Copyright

Trifluoroacetic Acid-catalysed Transacylation of Arenes by Acylpentamethylbenzene

Facile transacylation between acylpentamethylbenzene and activated arenes such as anisole was found to occur in boiling trifluoroacetic acid (TFA).The mechanism for the transacylation between acetylpentamethylbenzene (AcPMB) and anisole with TFA was elucidated by means of product isolation and kinetics.The reaction proceeds via reversible protodeacetylation of AcPMB involving an ipso-protonated intermediate B to give pentamethylbenzene and acetic trifluoroacetic anhydride followed by irreversible acetylation of anisole by the mixed anhydride.The mechanism resulting in an ipso-protonated intermediate B was deduced from the reaction of acetylmesitylene with TFA as well as from the rate of deacetylation of 3,5-dideuterioacetylmesitylene with TFA.The formation of such an intermediate was also independently confirmed by 13C n.m.r. spectroscopic syudies on AcPMB in superacid solutions under stable conditions.

Arene Activation with Mercury(II) and Thallium(III) Electrophiles. Mechanistic Relevance of Charge-Transfer Transitions in ?-Complexes as Intermediates

The activation of various aromatic hydrocarbons by mercuration and thallation proceeds via ?-complexes, as observed by the transient charge-transfer (CT) absorption spectra.Quantitative spectrophotometric analysis of (a) the association constants K and (b) the second-order rate constants k2 establishes the reactive forms of the electrophiles to be Hg(O2CCF3)2 and Tl(O2CCF3)2(1+), both in ?-complex formation as well as in aromatic metalation.The direct participation by these isoelectronic and isostructural species presents a unique opportunity to examine arene activation with electrophiles which primarily differ only in the charge they bear.A detailed comparison of the CT excitation energies and the reactivities of various arenes relative to steric, kinetic isotope, and solvent effects in mercuration and thallation reveals unusual similarities.At the same time the observation of arene cations as key intermediates in thallation, but not in mercuration, leads to puzzling incongruities.The paradox is analyzed in the context of merging stepwise (electron-transfer) and concerted (electrophilic) mechanisms.

Kinetics and Mechanism of Aromatic Thallation. Identification and Proof of Competiting Electrophilic and Electron-Transfer Pathways

The unusual occurrence of simultaneous electrophilic (two-electron) and electron-transfer (one-electron) pathways during the thallation of the homologous methylbenzenes ArCH3 is demonstrated by (1) the careful analysis and identification of three major types of products, (2) the complete dissection of the complex kinetics, and (3) the identification of the reactive intermediates by time-resolved UV-vis and ESR spectroscopy.Side-chain substitution S, dimerization D, and oxidative nuclear substitution O derive from the radical cation ArCH3+. produced as a common intermediate by electron transfer from the methylbenzene to thallium(III) trifluoroacetate in trifluoroacetic acid.The importance of ArCH3+., which is detected by both its electronic and ESR spectra, decreases in the following order, hexamethylbenzene > pentamethylbenzene > durene >> mesitylene, with a concomitant rise in electrophilic nuclear thallation R to account for the complete material balance.The striking color changes that accompany thallation are identified as charge-transfer transition in the series of transient 1:1 ?-complexes of the methylbenzene donors and the thallium(III) acceptor.Quantitative spectrophotometry employing the Benesi-Hildebrand analysis establishes the cationic Tl(O2CCF3)2+ formed by the dissociation of a single trifluoroacetate ligand from the parent thallium tris(trifluoroacetate) as the active electron acceptor.The complete analysis of the complex kinetics including kinetic isotope effects with accompany the nuclear thallation R of mesitylene as well the side-chain substitution S of hexamethylbenzene shows that the cationic Tl(O2CCF3)2+ also serves the dual function as the active electrophile and the active oxidant, respectively.The close competition between these apparently disparate pathways is quantitatively evaluated by the second-order rate constants which differ by less than an order of magnitude.Therefore, the thallation of arometic hydrocarbons represents one of the few systems in which such dual pathways, electrophilic and free radical, apparently occur side under the same experimental conditions of solvent, temperature, etc.Accordingly, it represents an unusual opportunity to delineate two-electron (concerted, electrophilic) from one-electron (stepwise, free radical) mechanism-especially as two whether they represent parallel or sequential events.

Acetyl Exchange between Acetyl Chloride and Sterically Hindered Aryl Ketones under Friedel-Crafts Condition

The kinetics of acetyl exchange between acetylmesitylene, or acetyldurene, and (14)C-labelled acetyl chloride have been measured in nitromethane solution in the presence of aluminium chloride.Mechanistic studies using acetylmesitylene as substrate show conclusively that acetyl exchange proceeds, not by acylation-deacylation or deacylation-acylation, but via a synchronous reaction involving an ipso-complex.Theoretical calculations (MNDO) indicate that of three possible synchronous pathways, two are energitically feasible.