13148-18-0

Upstream product

• 6261-32-1 2-benzylidene-1-tetralone 
• 7732-18-5 water 
• 7722-84-1 dihydrogen peroxide 
• 6261-32-1 (E)-2-benzylidene-1-tetralone 
• 49545-70-2 2-(4-chlorobenzylidene)-3,4-dihydronaphthalen-1(2H)-one 
• 17215-80-4 2-chloro-1-tetralone 
• 100-52-7 benzaldehyde 

Downstream Products

• 162130-65-6 4-(3-Phenyl-4,5-dihydro-benzo[g]indazol-2-yl)-benzenesulfonamide 
• 13243-59-9 2-Phenyl-4,5-benzo-cyclohepten-1,3-dion 
• 4024-14-0 1-methyl-2-tetralone 
• 107924-56-1 2-hydroxy-2-(α-methoxy-benzyl)-3,4-dihydro-2H-naphthalen-1-one 
• 78604-93-0 1,3-diphenyl-4,5-dihydro-1H-benzo[g]indazole 

Relevant academic research and scientific papers

Asymmetric epoxidation of a geminally-disubstituted and some trisubstituted enones catalysed by poly-L-leucine

Epoxidation of a range of enones derived from tetralone or related cyclic ketones, employing poly-L-leucine, urea-H2O2 and DBU in iso-propyl acetate is reported. The corresponding epoxides were isolated in 63-85% yield and 59-96% ee.

Polyamino acids as catalysts in asymmetric synthesis

The use of polyamino acids in asymmetric organic synthesis is reviewed. Particular emphasis is placed on the asymmetric epoxidation of α,β- unsaturated ketones with hydrogen peroxide in the presence of polyalanine or polyleucine, and further transformatio

A porphyrin-inspired iron catalyst for asymmetric epoxidation of electron-deficient olefins

An in situ formed porphyrin-inspired iron complex that catalyzes asymmetric epoxidation of di- and trisubstituted enones is described. The reaction provides highly enantioenriched α,β-epoxyketones (up to 99% ee). The practical utility of the new catalyst

Polyamino acid-catalysed asymmetric epoxidation: Sodium percarbonate as a source of base and oxidant

New reaction conditions, using sodium percarbonate, are reported for the polyamino acid-catalysed asymmetric epoxidation of enones. Under these new conditions the rate of the uncatalysed reaction is reduced allowing an increased ratio of substrate to catalyst compared with previous protocols.

Asymmetric Epoxidation of Olefins Catalyzed by Substituted Aminobenzimidazole Manganese Complexes Derived from L-Proline

A family of manganese complexes [Mn(Rpeb)(OTf)2] (peb=1-(1-ethyl-1H-benzo[d]imidazol-2-yl)-N-((1-((1-ethyl-1H-benzo[d]imidazol-2-yl)methyl) pyrrolidin-2-yl)methyl)-N-methylmethanamine)) derived from L-proline has been synthesized and characterized, where R refers to the group at the diamine backbone. X-ray crystallographic analyses indicate that all the manganese complexes [Mn(Rpeb)(OTf)2] exhibit cis-α topology. These types of complexes are shown to catalyze the asymmetric epoxidation of olefins employing H2O2 as a terminal oxidant with up to 96% ee. Obviously, the R group of the diamine backbone can influence the catalytic activity and enantioselectivity in the asymmetric epoxidation of olefins. In particular, Mn(i-Prpeb)(OTf)2 bearing an isopropyl arm, cannot catalyze the epoxidation reaction with H2O2 as the oxidant. However, when PhI(OAc)2 is used as the oxidant instead, all the manganese complexes including Mn(i-Prpeb)(OTf)2 can promote the epoxidation reactions efficiently. Taken together, these results indicate that isopropyl substitution on the Rpeb ligand inhibits the formation of active Mn(V)-oxo species in the H2O2/carboxylic acid system via an acid-assisted pathway.

Asymmetric Epoxidation of Enones Promoted by Dinuclear Magnesium Catalyst

Asymmetric synthesis with cheaper and non-toxic alkaline earth metal catalysts is becoming an important and sustainable alternative to conventional catalytic methodologies mostly relying on precious metals. In spite of some sustainable methods for enantioselective epoxidation of enones, the development of a well-defined and efficient catalyst based on magnesium complexes for these reactions is still a challenging task. In this perspective, we present the application of chiral dinuclear magnesium complexes for asymmetric epoxidation of a broad range of electron-deficient enones. We demonstrate that the in situ generated magnesium-ProPhenol complex affords enantioenriched oxiranes in high yields and with excellent enantioselectivities (up to 99% ee). Our extensive study verifies the literature data in this area and provides a step forward to better understand the factors controlling the oxygenation process. Elaborated catalyst offers mild reaction conditions and a truly wide substrate scope. (Figure presented.).

Br?nsted Base-Catalyzed Transformation of α,β-Epoxyketones Utilizing [1,2]-Phospha-Brook Rearrangement for the Synthesis of Allylic Alcohols Having a Tetrasubstituted Alkene Moiety

A stereoselective transformation of α,β-epoxyketones into alkenylphosphates having a hydroxymethyl group on the β-carbon was established by utilizing the [1,2]-phospha-Brook rearrangement under Br?nsted base catalysis. The reaction involves the catalytic generation of an α-oxygenated carbanion located at the α-position of an epoxide moiety through the [1,2]-phospha-Brook rearrangement and the following epoxide opening. Further transformation of the alkenylphosphates by the palladium-catalyzed cross-coupling reaction with Grignard reagents provided allylic alcohols having a stereodefined all-carbon tetrasubstituted alkene moiety.

The Synthesis of Hydrobenzoin-Based Monoaza Crown Ethers and Their Application as Recyclable Enantioselective Catalysts

Abstract: New recyclable monoaza-15-crown ethers have been synthesized starting from (R,R)-(+)- and (S,S)-(?)-hydrobenzoin. These macrocycles proved to be efficient and reusable phase transfer catalysts in a few asymmetric reactions under mild conditions.

Synthesis of xylal- and arabinal-based crown ethers and their application as asymmetric phase transfer catalysts

New xylal- and arabinal-based monoaza-15-crown-5 ethers were synthesized starting from l- and d-xylose, and l- and d-arabinose, respectively. These monosaccharide-based chiral macrocycles were tested as phase transfer catalysts in a few asymmetric reactions. The xylal-based crown compounds proved to be efficient catalysts in a few liquid-liquid phase reactions. The epoxidation of trans-chalcone and the Darzens condensation of α-chloroacetophenone with benzaldehyde took place with complete diastereoselectivity and up to 77% ee and 58% ee, respectively. It was found that the substituents in the aromatic ring of the chalcone and the α-chloroacetophenone had an influence on the enantioselectivity. The highest ee values were obtained in the epoxidation of 4-chlorochalcone (81% ee) and in the reaction of a 2-naphthyl analogue (96% ee), while in the Darzens condensation of 4-phenyl-α-chloroacetophenone with benzaldehyde, a maximum ee of 91% was detected. The configuration of the monosaccharide unit in the crown ring influenced the absolute configuration of the epoxyketones synthesized.

Highly enantioselective epoxidation of olefins by H2O2 catalyzed by a non-heme Fe(ii) catalyst of a chiral tetradentate ligand

The chiral tetradentate N4-donor ligand, 1-methyl-2-({(S)-2-[(S)-1-(1-methylbenzimidazol-2-yl methyl)pyrrolidin-2-yl]pyrrolidin-1-yl}methyl) benzimidazole (S,S-PDBzL), based on a chiral dipyrrolidine backbone, has been synthesized and its corresponding Fe(ii) complex has been prepared and characterized. The X-ray structure of the complex reveals that the Fe(ii) ion is in a distorted octahedral coordination environment with two cis-oriented coordination sites occupied by (labile) triflate anions. The ability of the iron complex to catalyze asymmetric epoxidation reactions of olefins with H2O2 was investigated, using 2-cyclohexen-1-one, 2-cyclopenten-1-one, cis-β-methylstyrene, isophorone, chalcones and tetralones as substrates. Different carboxylic acids were used as additives to enhance yields and enantioselectivities, and 2-ethylhexanoic acid was found to give the best results. The catalysis results indicate that the Fe(ii) complex is capable of effecting comparatively high enantioselectivities (>80%) in the epoxidation reactions.