71776-58-4

Upstream product

• 89-98-5 2-chloro-benzaldehyde 
• 21854-95-5 2,2'-dichlorobenzil 
• 25144-38-1 (E)-2,2'-dichlorostilbene 
• 611-17-6 1-bromomethyl-2-chlorobenzene 
• 17849-38-6 2-Chlorobenzyl alcohol 
• 95-49-8 2-methylchlorobenzene 
• 10577-21-6 1,2-Bis(2-chlorophenyl)-1-chloroethane 
• 35190-16-0 2,2'-dichlorobenzoin 

Downstream Products

• 84574-53-8 (2S,3S,5R,6R)-2,3,5,6-Tetrakis-(2-chloro-phenyl)-[1,4]dioxane 
• 84574-54-9 (2S,3R,5S,6R)-2,3,5,6-Tetrakis-(2-chloro-phenyl)-[1,4]dioxane 
• 929219-24-9 4,5-bis(2-chlorophenyl)-2-[4-(3-chloropropoxy)phenyl]-1,3-dioxolane 
• 668991-40-0 (S)-1,2-bis-(2-chloro-phenyl)-2-hydroxy-ethanone 
• 249626-07-1 (R)-1,2-bis(2-chlorophenyl)-2-hydroxyethan-1-one 

Relevant academic research and scientific papers

Oxidative carbon-carbon bond cleavage of 1,2-diols to carboxylic acids/ketones by an inorganic-ligand supported iron catalyst

The carbon-carbon bond cleavage of 1,2-diols is an important chemical transformation. Although traditional stoichiometric and catalytic oxidation methods have been widely used for this transformation, an efficient and valuable method should be further explored from the views of reusable catalysts, less waste, and convenient procedures. Herein an inorganic-ligand supported iron catalyst (NH4)3[FeMo6O18(OH)6]·7H2O was described as a heterogeneous molecular catalyst in acetic acid for this transformation in which hydrogen peroxide was used as the terminal oxidant. Under the optimized reaction conditions, carbon-carbon bond cleavage of 1,2-diols could be achieved in almost all cases and carboxylic acids or ketones could be afforded with a high conversion rate and high selectivity. Furthermore, the catalytic system was used efficiently to degrade renewable biomass oleic acid. Mechanistic insights based on the observation of the possible intermediates and control experiments are presented.

Crystal-to-Crystal Synthesis of Photocatalytic Metal–Organic Frameworks for Visible-Light Reductive Coupling and Mechanistic Investigations

Postmodification of reticular materials with well-defined catalysts is an appealing approach to produce new catalytic functional materials with improved stability and recyclability, but also to study catalysis in confined spaces. A promising strategy to this end is the postfunctionalization of crystalline and robust metal–organic frameworks (MOFs) to exploit the potential of crystal-to-crystal transformations for further characterization of the catalysts. In this regard, two new photocatalytic materials, MOF-520-PC1 and MOF-520-PC2, are straightforwardly obtained by the postfunctionalization of MOF-520 with perylene-3-carboxylic acid (PC1) and perylene-3-butyric acid (PC2). The single crystal-to-crystal transformation yielded the X-ray diffraction structure of catalytic MOF-520-PC2. The well-defined disposition of the perylenes inside the MOF served as suitable model systems to gain insights into the photophysical properties and mechanism by combining steady-state, time-resolved, and transient absorption spectroscopy. The resulting materials are active organophotoredox catalysts in the reductive dimerization of aromatic aldehydes, benzophenones, and imines under mild reaction conditions. Moreover, MOF-520-PC2 can be applied for synthesizing gram-scale quantities of products in continuous-flow conditions under steady-state light irradiation. This work provides an alternative approach for the construction of well-defined, metal-free, MOF-based catalysts.

Chiral Benzoins via Asymmetric Transfer Hemihydrogenation of Benzils: The Detail that Matters

The synthesis of enantiomerically pure benzoins by hydrogenation of readily available benzils has been long thwarted by their base-sensitivity. We show here that an iron(II) hydride complex catalyzes the asymmetric transfer hydrogenation of benzils from 2-propanol. When strictly base-free conditions are granted, excellent enantioselectivity is achieved even with o-substituted substrates, which are particularly challenging to prepare with other methods. Hence, under optimized reaction conditions, chiral benzoins were prepared in good yields (up to 83%) and excellent enantioselectivity (up to 98% ee) in short reaction times (30-75 min). Also, this work confirms that both enantiomers of the benzoin products can be accessed when a metal catalyst is used, which is a clear advantage over enzymatic methods.

Application of coumarin dyes for organic photoredox catalysis

Here we report the application of readily prepared and available coumarin dyes for photoredox catalysis, which are able to mimic powerful reductant [Ir(iii)] complexes. Coumarin derivatives 9 and 10 were employed as photoreductants in pinacol coupling and in other reactions, in the presence of Et3N as a sacrificial reducing agent. As the electronic, photophysical, and steric properties of coumarins could be varied, a wide applicability to several classes of photoredox reactions is predicted.

MeOH or H2O as efficient additive to switch the reactivity of allylSmBr towards carbonyl compounds

A variety of carbonyl compounds were treated by allylSmBr (allylSmBr) with MeOH as the cosolvent to have further insights on the previously reported reductive coupling of aryl ketones mediated by Sm/alkyl halide/MeOH. The results demonstrate that the real reducing species in Sm/alkyl halide/MeOH system should be allylSmBr, and MeOH has elegantly switched the reactivity of allylSmBr from being nucleophilic to being good reductive coupling reagent. Besides, H2O was also found to be a useful additive to realize the pinacol coupling of aliphatic aldehydes and ketones promoted by allylSmBr.

Copper-catalyzed double intramolecular ullmann coupling for the synthesis of diastereomerically and enantiomerically pure 4b,9b-dihydrobenzofuro[3,2-b]benzofurans

The copper-catalyzed double intramolecular Ullmann coupling of syn-1,2-bis(2-bromoaryl)ethane-1,2-diols with catalytic amounts of CuII oxinate as the copper source, K3PO4 as a base, and KI as a reductant in aqueous acetoni

Selective Pinacol Coupling on Regeneratable Supported Acids in Sole Water

Efficient pinacol coupling was developed in sole water, using a reusable heterogeneous supported acid source and zinc as cheap available metal source. This medium can be easily regenerated up to 10-fold without loss of activity. Moreover, supported acids enhance the selectivity of the pinacol coupling reaction compared with homogeneous acids.

Biocatalyzed asymmetric reduction of benzils to either benzoins or hydrobenzoins: pH dependent switch

Enantiopure benzoins and hydrobenzoins are precursors of various pharmaceuticals and biologically active compounds. In addition, hydrobenzoins are precursors of chiral ligands and auxiliaries in stereoselective organic synthesis. Biocatalytic reduction of benzils is a straightforward approach to prepare these molecules. However, known methods are not selective and lead to formation of a mixture of benzoin and hydrobenzoin, requiring expensive separation procedures. Here, we describe an enzyme system Talaromyces flavus, which exhibited excellent pH dependent selectivity for the conversion of benzil to either benzoin or hydrobenzion in high ee. Thus, (S)-benzoin was the exclusive product at pH 5.0 (ee >99%), whereas at pH 7.0, (S,S)-hydrobenzoin (ee >99%, dl/meso 97 : 3) was the exclusive product. The observed pH dependent selectivity was shown to be due to the presence of multiple enzymes in Talaromyces flavus, which specifically accepted either benzil or benzoin as a substrate and exhibited different pH profiles of their activity. The biocatalyst efficiently reduced a variety of symmetrical and unsymmetrical benzils. Moreover, a 36.4 kDa benzoin reductase was purified, the N-terminal sequence of which did not show a significant similarity to any of the known reductase/dehydrogenase in the database. The protein therefore appears to be a novel reductase.

The scalable pinacol coupling reaction utilizing the inorganic electride [Ca2N]+·e- as an electron donor

The scalable pinacol coupling reaction is realized utilizing the inorganic electride [Ca2N]+·e- as an electron donor in organic solvents. The bond cleavages of the [Ca2N] + layers by methanol play a vital role in transferring anionic electrons to electrophilic aldehydes, accompanying the formation of Ca(OMe) 2 and ammonia. The Royal Society of Chemistry 2014.

Reductive coupling of aromatic aldehydes and acetophenone induced by TiCl4-Al/CH2(COOEt)2

Induced by TiCl4-Al/CH2(COOEt)2 in CH 2Cl2, some aromatic aldehydes and acetophenone can afford the corresponding 1,2-diols in 13-91 % yields with good dl- diastereoselectivities within 45-60 min at room temperature.