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Upstream product

• 634-36-6 1,2,3-trimethoxybenzene 
• 151-10-0 1,3-Dimethoxybenzene 
• 7789-20-0 water-d2 
• 34584-49-1 2.6-dimethoxyphenyl silver 
• 16932-44-8 2-iodo-1,3-dimethoxybenzene 
• 1466-76-8 2-6-dimethoxybenzoic acid 

Downstream Products

• 151-10-0 1,3-Dimethoxybenzene 

Relevant academic research and scientific papers

Exploiting a silver-bismuth hybrid material as heterogeneous noble metal catalyst for decarboxylations and decarboxylative deuterations of carboxylic acids under batch and continuous flow conditions

Herein, we report novel catalytic methodologies for protodecarboxylations and decarboxylative deuterations of carboxylic acids utilizing a silver-containing hybrid material as a heterogeneous noble metal catalyst. After an initial batch method development, a chemically intensified continuous flow process was established in a simple packed-bed system which enabled gram-scale protodecarboxlyations without detectable structural degradation of the catalyst. The scope and applicability of the batch and flow processes were demonstrated through decarboxylations of a diverse set of aromatic carboxylic acids. Catalytic decarboxylative deuterations were achieved on the basis of the reaction conditions developed for the protodecarboxylations using D2O as a readily available deuterium source.

Nickel-Catalyzed Deoxygenative Deuteration of Aryl Sulfamates

The nickel-catalyzed deoxygenative deuteration of aryl/heteroaryl sulfamates has been developed, and the effective incorporation of deuterium into a variety of aromatic compounds was achieved with sufficient catalytic efficiency and high deuteration degree. This process tolerated reducible functional moieties and heterocyclic structures. Additionally, a double introduction of deuterium also successfully gave a desired product with a high yield and deuterium content. (Figure presented.).

Sodium Diisopropylamide in Tetrahydrofuran: Selectivities, Rates, and Mechanisms of Arene Metalations

Sodium diisopropylamide (NaDA)-mediated metalations of arenes in tetrahydrofuran (THF)/hexane or THF/Me2NEt solutions are described. A survey of >40 benzenoid- and pyridine-based arenes with a range of substituents demonstrates the efficacy and regioselectivity of metalation. Metalations of activated disubstituted arenes and selected monosubstituted arenes are rapid at -78 °C. Rate studies of 1,3-dimethoxybenzene and related methoxylated arenes show exclusively monomer-based orthometalations with two or three coordinated THF ligands. Rate studies of the isotopic exchange of benzene and monosubstituted arenes with weakly activating groups reveal analogous di- and trisolvated monomer-based metalations. Cooperative inductive, mesomeric, steric, and chelate effects are discussed.

Selective copper- or silver-catalyzed decarboxylative deuteration of aromatic carboxylic acids

The practical utility of decarboxylative transformations in organic synthesis is discussed, and the decarboxylative deuteration of (hetero)aromatic carboxylic acids is disclosed as a further example. Various monodeuterated arenes were synthesized under mild conditions, in a single step from easily accessible aromatic carboxylic acids and deuterium oxide. Copper catalysts were found to have the widest scope, but silver catalysts are superior for some ortho-substituted benzoates. A few substrates, e.g. quinoline-2-carboxylic acid, decarboxylate even in the absence of a metal catalyst. Georg Thieme Verlag Stuttgart · New York.

Halogen-deuterium exchange reaction mediated by tributyltin hydride using THF-d8 as the deuterium source

A regioselective deuteration method for a wide variety of aromatic compounds using the halogen-deuterium exchange reaction initiated by Bu 3SnH using THF-d8 as the deuterium source was developed.

Microwave enhanced decarboxylations of aromatic carboxylic acids: Improved deuteriation/tritiation potential

Decarboxylation of aromatic carboxylic acids under microwave enhanced conditions is an increasingly attractive method of preparing deuterium/tritium labelled compounds.

Photochemistry of Dimethoxybenzenes in Aqueous Sulfuric Acid

The photochemistry of the three isomeric dimethoxybenzenes (1-3) has been studied in aqueous sulfuric acid.Two processes were found to take place: (i) photoprotonation of the ring resulting in exchange of the ring protons, which was observed for all three compounds and (ii) ipso substitution of the methoxy group by water, which was observed only for 1,2-dimethoxybenzene (3).Both of these photochemical reactions were catalyzed by acid, requiring acidities stronger than pH(D)2 for observable reaction.Quantum yields for proton exchange and ipso substitution are reported as a function of medium acidity.The fluorescence emissions of all three compounds were quenched by acid, to give sigmoid type quenching curves, that have a complementary relationship with the corresponding plots of quantum yield of exchange vs acidity, consistent with protonation of the benzene ring in S1 as the primary photochemical step, to give cyclohexadienyl cation intermediates.Stern-Volmer analysis of fluorescence quenching by proton gave photoprotonation rates in the range 0.09-2.2*109 M-1 s-1.The results of this work demonstrate unambiguously that methoxy-substituted benzenes are much stronger bases in S1 (pKBH+ ca. 1 to -2) than in the ground state.This enhanced basicity is manifested in regioselectivity of exchange of 1 and 3 and ipso substitution chemistry of 3, processes not observed in the ground states of these compounds.

Regioselective Reductive Electrophilic Substitution of 1,2,3-Trimethoxybenzene and Its 5-Alkyl-Substituted Homologues

The methoxy group in the 2-position of 1,2,3-trimethoxybenzene (1) can be regioselectively removed by electron transfer from alkali metals and replaced with a variety of electrophiles in a one-pot procedure, affording 2-substituted resorcinol dimethyl ethers.The usefulness of this synthetic method is illustrated by numerous examples.This reaction procedure has been successfully extended to the 5-methyl-substituted homologue (2), but limitations occur with the higher homologue 1-pentyl-3,4,5-trimethoxybenzene (3).Investigations on the mechanism of demethoxylation, with the aid of labeling experiments, provided clear evidence for the intermediacy of aryl radicals and explained the low yields obtained in the reductive electrophilic substitution of compound 3.

REGIOSELECTIVE REDUCTIVE ALKYLATION OF 1,2,3-TRIMETHOXYBENZENE

The 2-methoxyl group of 1,2,3-trimethoxybenzene and its 5-methyl-substituted homologue is removed under electron transfer conditions and replaced with an alkyl group in a one-pot procedure.