57412-90-5

Upstream product

• 108-88-3 toluene 

Relevant academic research and scientific papers

Iron-catalysed tritiation of pharmaceuticals

A thorough understanding of the pharmacokinetic and pharmacodynamic properties of a drug in animal models is a critical component of drug discovery and development. Such studies are performed in vivo and in vitro at various stages of the development process-ranging from preclinical absorption, distribution, metabolism and excretion (ADME) studies to late-stage human clinical trials-to elucidate a drug molecule's metabolic profile and to assess its toxicity. Radiolabelled compounds, typically those that contain 14C or 3H isotopes, are one of the most powerful and widely deployed diagnostics for these studies. The introduction of radiolabels using synthetic chemistry enables the direct tracing of the drug molecule without substantially altering its structure or function. The ubiquity of C-H bonds in drugs and the relative ease and low cost associated with tritium (3H) make it an ideal radioisotope with which to conduct ADME studies early in the drug development process. Here we describe an iron-catalysed method for the direct 3H labelling of pharmaceuticals by hydrogen isotope exchange, using tritium gas as the source of the radioisotope. The site selectivity of the iron catalyst is orthogonal to currently used iridium catalysts and allows isotopic labelling of complementary positions in drug molecules, providing a new diagnostic tool in drug development.

Facile H/D exchange at (hetero)aromatic hydrocarbons catalyzed by a stable trans-dihydride n-heterocyclic carbene (NHC) iron complex

Earth-abundant metal pincer complexes have played an important role in homogeneous catalysis during the last ten years. Yet, despite intense research efforts, the synthesis of iron PCcarbeneP pincer complexes has so far remained elusive. Here we report the synthesis of the first PCNHCP functionalized iron complex [(PCNHCP)FeCl2] (1) and the reactivity of the corresponding trans-dihydride iron(II) dinitrogen complex [(PCNHCP)- Fe(H)2N2)] (2). Complex 2 is stable under an atmosphere of N2 and is highly active for hydrogen isotope exchange at (hetero)aromatic hydrocarbons under mild conditions (50 °C, N2). With benzene-d6 as the deuterium source, easily reducible functional groups such as esters and amides are well tolerated, contributing to the overall wide substrate scope (e.g., halides, ethers, and amines). DFT studies suggest a complex assisted σ-bond metathesis pathway for C(sp2)-H bond activation, which is further discussed in this study.

H/D exchange processes catalyzed by an iridium-pincer complex

A PNP-pincer iridium dihydride performs the H/D exchange between aromatic substrates and tertiary hydrosilanes and D2O or C6D 6. Complete incorporation of deuterium into sterically accessible Car-H and Si-H bonds was observed at a moderate temperature of 80 °C.

Ruthenium dihydrogen complex for C-H activation: Catalytic H/D exchange under mild conditions

Catalytic H/D-exchange reactions were studied with [Ru(dtbpmp) (η2-H2)(H)2] (1) as catalyst. Under mild reaction conditions (25-75°C) a wide range of arenes and olefins undergo H/D exchange with [D6]benzene. A p

H/D exchange at aromatic and heteroaromatic hydrocarbons using D 2O as the deuterium source and ruthenium dihydrogen complexes as the catalyst

Getting heavy: At temperatures as low as 50°C, D2O can serve as a cheap and readily available deuterium source for the efficient deuteration of aromatic and heteroaromatic substrates if nonclassical ruthenium hydride complexes are used as catalysts (see scheme). DFT calculations support a catalytic cycle comprising σ-bond metathesis as the key step for the exchange processes. (Chemical Equation Presented).

The remarkable electron impact mass spectrum of (2-benzyl-1,3-xylylene)-15- crown-4: Expulsion of triethylene glycol by double hydrogen transfer

During our investigations of the synthesis of magnesium-containing crown ethers, the mass spectral characterisation of a precursor, (2-benzyl-1,3- xylylene)-15-crown-4 (C21H26O4), leads to a surprising result: its electron