182621-75-6

Upstream product

• 536-38-9 4-chlorobenzoylmethyl bromide 
• 37577-28-9 (1S,2R)-(+)-norphedrine 
• 33491-03-1 1-(bromoethynyl)-4-chlorobenzene 
• 1073-67-2 4-vinylbenzyl chloride 
• 108-05-4 vinyl acetate 
• 6314-52-9 2-bromo-1-(4-chlorophenyl)ethanol 
• 6529-53-9 1-(2-bromoethyl)-4-chlorobenzene 
• 1875-88-3 2-(4-Chlorophenyl)ethanol 
• 22651-87-2 cyclohexanecarboxylic acid anhydride 

Downstream Products

• 2788-86-5 (R)-2-(4-chlorophenyl)oxirane 
• 6314-62-1 C₁₅H₁₆ClNO 

Relevant academic research and scientific papers

Chiral guanidine catalyzed acylative kinetic resolution of racemic 2-bromo-1-arylethanols

In this study, chiral guanidine catalyzed acylative kinetic resolution of racemic 2-bromo-1-arylethanols was achieved with high selectivity. Irrespective of the electronic nature and the substitution patterns on the aromatic rings, a variety of substrates were suitable for this reaction. The branched acyl component was considered to be optimal for obtaining high s-values. The transition state of the reaction was proposed based on the absolute configuration of the obtained product.

Asymmetric synthesis of α-bromohydrins by carrot root as biocatalyst and conversion to enantiopure β-hydroxytriazoles and styrene oxides using click chemistry and SN2 ring-closure

In this study we have combined the bioreduction of α-bromoketones using carrot root as biocatalyst and click chemistry for the preparation of enantiopure β-hydroxytriazoles in excellent enantiomeric excesses and yields. Moreover, we have utilized chiral α-halohydrins for the synthesis of enantiopure styrene oxides in very good yields and enantiomeric excesses. Structural assignments of the products were based on their 1H and 13C NMR data and their optical rotations. The enantiomeric excess of the chiral products was obtained by HPLC analysis.

Cascade bio-hydroxylation and dehalogenation for one-pot enantioselective synthesis of optically active β-halohydrins from halohydrocarbons

A stereoselective hydroxylation and enantioselective dehalogenation cascade reaction was developed for the synthesis of optically active β-haloalcohols from halohydrocarbons. This cascade system employed P450 and halohydrin dehalogenase as two compatible biocatalysts, allowing a straightforward, greener and efficient access to β-halohydrins with excellent enantioselectivities (98-99%).

Selective Asymmetric Transfer Hydrogenation of α-Substituted Acetophenones with Bifunctional Oxo-Tethered Ruthenium(II) Catalysts

A practical method for the asymmetric transfer hydrogenation of α-substituted ketones was developed utilizing oxo-tethered N-sulfonyldiamine-ruthenium complexes. Reduction by HCO2H and HCO2K in a mixed solvent of EtOAc/H2O allowed for the selective synthesis of halohydrins from 2-bromoacetophenone (98%) and 2-chloroacetophenone (>99%), leading to suppressed undesired side reactions stemming from formylation under the typical reaction conditions using an azeotropic 5:2 mixture of HCO2H and Et3N. A range of functional groups, such as halogens, methoxy, nitro, dimethylamino, and ester groups, were well tolerated, highlighting the potential of this method. Nearly complete selectivity with a preferable ee was maintained even with a substrate/catalyst (S/C) ratio of 5000. This catalyst system was also effective for the asymmetric reduction of α-sulfonated ketones without eroding the leaving group. (Figure presented.).

Immobilization of Amano lipase from Pseudomonas fluorescens on silk fibroin spheres: an alternative protocol for the enantioselective synthesis of halohydrins

The search for a new, efficient, cheaper and sustainable matrix for lipase immobilization is a growing area in biotechnology. Amano lipase from Pseudomonas fluorescens was immobilized on silk fibroin spheres and used in the enzymatic kinetic resolution of halohydrins, to obtain optically active epoxides (up to 99% ee), important precursors in the synthesis of derivative antifungal azoles. This paper reinforces the versatility of silk fibroin as a support for heterogeneous catalysts.

Integration of multiple active sites on large-pore mesoporous silica for enantioselective tandem reactions

Facile construction of a multifunctional heterogeneous catalyst through the assembly of Au/carbene and chiral ruthenium/diamine dual complexes in large-pore mesoporous silica was developed. This enables an efficient one-pot hydration-asymmetric transfer hydrogenation enantioselective tandem reaction of haloalkynes, affording chiral halohydrins with up to 99% enantioselectivity. Combined multifunctionalities, such as substrate-promoted silanol-functionality, BF4? anion-bonding gold/carbene and covalent-bonding chiral ruthenium/diamine active centers, contributed cooperatively to the catalytic performance.

A preparation method of the compound hydroxy bromine

The present invention discloses a hydroxyl bromine compound preparation method comprising the following steps: in the presence of a catalyst, a compound shown as the formula I and N-brombenzamide are reacted in a liquid mixture of an organic solvent and water to obtain a compound shown as the formula II, wherein R1 are hydrogen or C1-C3 alkyl group; R2 are hydrogen or C1-C3 alkyl group; and R3 are hydrogen or C1-C4 alkyl group. A styrene type substrate and the N-brombenzamide are used as raw materials for effectively synthesizing a series of hydroxyl bromine compounds in the effect of (DHQD) 2PHAL. The raw materials are simple and easy to get, the nucleophile water is non-toxic and harmless, reaction conditions are mild, operation is simple, the method is atomic economic, enantiomer excess can reach up to 88%, the yield can reach up to 94%, the compounds has regioselectivity completely different from that of epoxy ring opening products, meanwhile the introduced C-Br bond and C-O bond both can be further transformed, and the method has great value.

Catalytic Asymmetric Bromination of Unfunctionalized Olefins with H2O as a Nucleophile

The dimeric cinchona alkaloid (DHQD)2PHAL is used to catalyze an effective asymmetric bromohydroxylation of unfunctionalized olefins with H2O as nucleophile an N-bromobenzamide as a bromine source. A variety of optically active bromohydrins are formed with up to 88%ee. PHAL's positive: An effective asymmetric bromohydroxylation of unfunctionalized olefins with H2O as nucleophile catalyzed by the dimeric cinchona alkaloid (DHQD)2PHAL (see scheme) is described. Optically active bromohydrins are obtained with up to 88%ee.

One-Pot cascade hydration-asymmetric transfer hydrogenation as a practical strategy to construct chiral β-adrenergic receptor blockers

The facile construction of biologically active β-adrenergic receptor agonists/blockers and analogues is a great fundamental and practical challenge in medical chemistry. Herein, we report a hydration-asymmetric transfer hydrogenation cascade to realize the one-pot enantioselective transformation of aromatic haloalkynes into chiral aromatic halohydrins, which can be converted readily into chiral β-adrenergicreceptor blockers. Such a one-pot cascade process involves the Au-catalyzed hydration of aryl-substituted haloalkynes to aryl-substituted α-halomethyl ketones and the Ru-catalyzed asymmetric transfer hydrogenation of aryl-substituted α-halomethyl ketones to aryl-substituted 2-haloethanols. The significant benefits of this procedure are that it provides chiral aromatic halohydrins in high yields, with excellent enantioselectivities, and a wide variety of functional groups are tolerated under mild conditions. The study described herein offers a useful approach to construct chiral β-adrenergic blockers, which is an attractive practical organic transformation that is performed in a one-pot manner.

Unconserved substrate-binding sites direct the stereoselectivity of medium-chain alcohol dehydrogenase

Structure-guided design of substrate-binding pocket inversed the stereoselectivity of an NADH-dependent medium-chain alcohol dehydrogenase (MDR) from Prelog to anti-Prelog. The pocket-forming amino acids, especially the unconserved residues as hotspots, play critical roles in directing MDRs' stereoselectivity. This journal is the Partner Organisations 2014.