66701-19-7

Upstream product

• 98-87-3 benzylidene dichloride 
• 73447-13-9 potassium 4-chlorobenzyl oxide 
• 1657-49-4 1-chloro-4-styrylbenzene 
• 104-88-1 4-chlorobenzaldehyde 
• 134988-30-0 benzyldibutyltelluronium bromide 
• 622-95-7 4-chlorobenzyl bromide 
• 75-21-8 oxirane 
• 908094-04-2 phenyldiazomethane 
• 75-18-3 dimethylsulfide 
• 100-39-0 benzyl bromide 
• 873-76-7 para-Chlorobenzyl alcohol 
• 100-52-7 benzaldehyde 
• 1080-32-6 O,O-diethyl benzylphosphonate 
• 1657-50-7 (E)-1-(4-chlorophenyl)-2-phenylethene 

Downstream Products

• 623-03-0 4-Cyanochlorobenzene 
• 104-88-1 4-chlorobenzaldehyde 
• 100-52-7 benzaldehyde 
• 100-47-0 benzonitrile 
• 134-85-0 4-chlorobenzophenone 
• 28523-15-1 2-(4-chlorophenyl)-2-phenylacetaldehyde 
• 6332-83-8 2-(4-chlorophenyl)-1-phenylethanone 
• 1889-71-0 4'-chloro-2-phenylacetophenone 

Relevant academic research and scientific papers

Method used for direct synthesis of epoxy compounds from alcohol

The invention discloses a method used for direct synthesis of an epoxy compounds from an alcohol. According to the method, an alcohol is taken as a raw material, Swern oxidation is adopted to synthesize an aldehyde, a bromo-hydrocarbon and an alkali are added into the aldehyde directly to construct epoxy functional groups, and generate the epoxy compound. According to the method, one-pot method is adopted to realize direct epoxidation of the alcohol, the synthesis route is simple, the preparation process is easy to control, no catalyst is needed in the process, substrate suitable range is wide, reagents are cheap and easily available, preparation conditions are mild, reaction yield is high, and the method is suitable for synthesis of epoxy compounds.

A non-heme iron(III) complex with porphyrin-like properties that catalyzes asymmetric epoxidation

In this report, we describe an iron(III) complex containing a carbazole-based tridentate ligand that catalyzes highly enantioselective asymmetric epoxidation of (E)-alkenes at room temperature. The non-heme iron(III) complex has a five-coordinated trigonal-bipyramidal structure, and its two-electron oxidized state has the similar electronic structure as that of iron porphyrins.

New camphor-derived selenonium ylides: Enantioselective synthesis of chiral epoxides

Optically pure selenonium salts 3 as the precursors of two new chiral selenonium ylides 4 can be synthesized stereoselectively from natural d-camphor in good yields. It is found that the reaction of the selenonium salt 3b, an aldehyde, and potassium tert-butoxide can take place smoothly in ?one-pot' via the formation of selenonium ylide 4b, to give chiral trans-diaryl epoxides 5 in good yields with good diastereoselectivities and enantioselectivities. CSIRO 2005.

Design of sulfides with a locked conformation as promoters of catalytic and asymmetric sulfonium ylide epoxidation

A new generation of 2,5-dimethylthiolanes with a locked conformation was developed to promote the asymmetric addition of chiral sulfonium ylides to aldehydes. The novel chiral sulfur derivative 4 succeeded the synthesis of trans-stilbene oxide derivatives with enantiomeric ratios ranging from 95:5 to 98:2. This user-friendly organocatalytic process proved to be efficient with 20-10% of sulfide 4 in 1 or 2 days of reaction. An insight into the ylide intermediate conformation is given on the basis of a computational ab initio study.

A novel and highly efficient asymmetric synthesis of epoxides via chiral telluronium ylides

The one-pot reaction of telluronium salt 8, aldehyde, and potassium tert-butoxide proceeded smoothly via chiral benzyl telluronium ylide, producing trans-(2S,3S)-diaryl epoxides with good yields as well as excellent diastereoselectivities and enantioselectivities (up to 99% ee). Georg Thieme Verlag Stuttgart.

Highly stereoselective synthesis of trans-diaryl epoxides via semi-stabilised telluronium ylide

Benzyldibutyltelluronium bromide can react with LDA to form benzyldibutyltelluronium ylide in situ, followed by the reaction with aromatic aldehydes, developed a novel method for the stereoselective synthesis of trans-diaryl epoxides.

Process for the preparation of an oxirane, aziridine or cyclopropane

A process for the preparation of an oxirane, aziridine or cyclopropane of formula (I), wherein X is oxygen, NR4or CHR5; R1is hydrogen, alkyl, aryl, heteroaromatic, heterocyclic or cycloalkyl; R2is hydrogen, alkyl, aryl, heteroaromatic, CO2R8, CHR14NHR13, heterocyclic or cycloalkyl; or R1and R2join together to form a cycloalkyl ring; R3and R10are, independently, hydrogen, alkyl, aryl, heteroaromatic, CO2R8, R83Sn, CONR8R9, trialkylsilyl or triarylsilyl; R4is an electron withdrawing group; R5is alkyl, cycloalkyl, aryl, heteroaromatic, SO2R8, SO3R8, COR8, CO2R8, CONR8R9, PO(R8)2, PO(OR8)2or CN; R8and R9are independently alkyl or aryl; and R13and R14are independently hydrogen, alkyl or aryl is provided. The process comprises degrading a compound of formula (II), (IIa), (IIb) or (IIc): wherein R3and R10are as defined above; Y is a cation; depending on the nature of Y, r is 1 or 2; and L is a suitable leaving group, to form a diazo compound. The diazo compound is reacted with a suitable transition metal catalyst, and the product thereof reacted with a sulphide of formula SR6R7, wherein R6and R7are independently alkyl, aryl or heteroaromatic, or R6and R7join together to form an optionally substituted ring which optionally includes an additional heteroatom. This product is then reacted with an aldehyde, ketone, imine or alkene.

A new protocol for the in situ generation of aromatic, heteroaromatic, and unsaturated diazo compounds and its application in catalytic and asymmetric epoxidation of carbonyl compounds. Extensive studies to map out scope and limitations, and rationalization of diastereo- and enantioselectivities

A variety of metalated tosylhydrazone salts derived from benzaldehyde have been prepared and were reacted with benzaldehyde in the presence of tetrahydrothiophene (THT) (20 mol %) and Rh2(OAc)4 (1 mol %) to give stilbene oxide. Of the lithium, sodium, and potassium salts tested, the sodium salt was found to give the highest yield and selectivity. This study was extended to a wide variety of aromatic, heteroaromatic, aliphatic, α,β-unsaturated, and acetylenic aldehydes and to ketones. On the whole, high yields of epoxides with moderate to very high diastereoselectivities were observed. A broad range of tosylhydrazone salts derived from aromatic, heteroaromatic, and α,β-unsaturated rated aldehydes was also examined using the same protocol in reactions with benzaldehyde, and again, good yields and high diastereoselectivities were observed in most cases. Thus, a general process for the in situ generation of diazo compounds from tosylhydrazone sodium salts has been established and applied in sulfur-ylide mediated epoxidation reactions. The chiral, camphor-derived, [2.2.1] bicyclic sulfide 7 was employed (at 5-20 mol % loading) to render the above processes asymmetric with a range of carbonyl compounds and tosylhydrazone sodium salts. Benzaldehyde tosylhydrazone sodium salt gave enantioselectivities of 91 ± 3% ee and high levels of diastereoselectivity with a range of aldehydes. However, tosylhydrazone salts derived from a range of carbonyl compounds gave more variable selectivities. Although those salts derived from electron-rich or neutral aldehydes gave high enantioselectivities, those derived from electron-deficient or hindered aromatic aldehydes gave somewhat reduced enantioselectivities. Using α,β-unsaturated hydrazones, chiral sulfide 7 gave epoxides with high diastereoselectivities, but only moderate yields were achieved (12-56%) with varying degrees of enantioselectivity. A study of solvent effects showed that, while the impact on enantioselectivity was small, the efficiency of diazo compound generation was influenced, and CH3CN and 1,4-dioxane emerged as the optimum solvents. A general rationalization of the factors that influence both relative and absolute stereochemistry for all of the different substrates is provided. Reversibility in formation of the betaine intermediate is an important issue in the control of diastereoselectivity. Hence, where low diastereocontrol was observed, the results have been rationalized in terms of the factors that contribute to the reduced reversion of the syn betaine back to the original starting materials. The enantioselectivity is governed by ylide conformation, facial selectivity in the ylide reaction, and, again, the degree of reversibility in betaine formation. From experimental evidence and calculations, it has been shown that sulfide 7 gives almost complete control of facial selectivity, and, hence, it is the ylide conformation and degree of reversibility that are responsible for the enantioselectivity observed. A simple test has been developed to ascertain whether the reduced enantioselectivity observed in particular cases is due to poor control in ylide conformation or due to partial reversibility in the formation of the betaine.

Experimental evidence for multiple oxidation pathways in the (salen)Mn-catalyzed epoxidation of alkenes

The substrate electronic effects on the selectivity in the catalytic epoxidation of para-substituted cis stilbenes 2a-i were investigated by using (R,R)-[N,N′-bis(3,5-di-tBu-salicylidene)-1,2-cyclohexanediamine] manganese(III) chloride 1 in benzene as the catalyst with iodosobenzene as the terminal oxidant. A Hammett study of the selectivity results reveals a stronger electrophilic character than previously assumed in the (salen)Mn-catalyzed reaction. In general, the best correlations with the experimental values were obtained by using the Hammett σ+ values, which gave ρ = -1.37 for the rate of cisepoxide formation and ρ = -0.43 for the rate of the stepwise process leading to the corresponding trans product. The reaction involves two separate pathways as indicated also by the competitive breakdown of the intermediate on the path to trans epoxide for methoxy-substituted substrates. The asynchronicity in the concerted pathway leading to cis epoxide is apparent for 4-methoxy-4′-nitrostilbene, which yields cis epoxide with 75% ee entirely as a result of electronic effects.

Asymmetric epoxidation of aldehydes catalyzed by new C2-symmetrical chiral sulfide

Asymmetric synthesis of chiral epoxides from various aldehydes with benzyl bromide was investigated using new C2-symmetrical chiral sulfides, which were readily prepared from (R,R)-tartaric acid.