75801-34-2

Upstream product

• 18869-29-9 (E)-4,4'-dimethylstilbene 
• 104-81-4 4-Methylbenzyl bromide 

Downstream Products

• 107245-96-5 (3R,5S)-3,5-Di-p-tolyl-[1,2,4]trioxolane 
• 107246-09-3 (2S,5R)-2,5-Di-p-tolyl-furan-3,3,4,4-tetracarbonitrile 
• 107246-10-6 (2R,5R)-2,5-Di-p-tolyl-furan-3,3,4,4-tetracarbonitrile 
• 104-87-0 4-methyl-benzaldehyde 
• 104-85-8 para-methylbenzonitrile 
• 3457-48-5 1,2-di(4-methylphenyl)-1,2-ethanedione 
• 4528-66-9 bis(4-methylphenyl)-acetaldehyde 

Relevant academic research and scientific papers

Synthesis of Epoxides from Alkyl Bromides and Alcohols with in Situ Generation of Dimethyl Sulfonium Ylide in DMSO Oxidations

Direct conversion of the readily available alkyl bromides and alcohols to value-added epoxides using dimethyl sulfoxide (DMSO) under mild reaction conditions has been developed. Benzyl and allyl bromides, and activated and unactivated alcohols all proceeded smoothly to give epoxides in high to excellent yield. Dimethyl sulfide, generated by DMSO oxidations, was in situ elaborated to form the substituted dimethyl sulfonium ylide species that participates in the Corey-Chaykovsky epoxidation in a domino and one-pot fashion, respectively.

Method for directly synthesizing epoxy compound from benzyl bromine compound

The invention discloses a method for directly synthesizing an epoxy compound from a benzyl bromine compound. According to the method, by using a benzyl bromine compound as a reactant and dimethyl sulfoxide as an oxidizing agent, an epoxy compound is directly synthesized under the action of a solvent and alkali. The synthetic route of the method is as follows: the benzyl bromine compound is dissolved in a reaction solvent to obtain A; the oxidizing agent dimethyl sulfoxide and alkali are added into the A and a reaction is carried out to obtain the epoxy compound. The method is simple and is convenient to operate; the reaction condition is mild; the reaction process is easy to control; the reaction process is safe and environmentally-friendly; the reaction reagents are cheap and easily available; and the reaction yield is high.

A biomimetic iron catalyst for the epoxidation of olefins with molecular oxygen at room temperature

It's no sacrifice: A bio-inspired iron system, in which a β-keto ester serves as a sacrificial cosubstrate, readily epoxidizes olefins under ambient conditions with air. Aromatic olefins are oxidized in high yields with excellent chemoselectivity. Mechanistic investigations point out substantial differences to well-known radical-based autoxidations.

Biomimetic iron-catalyzed asymmetric epoxidation of aromatic alkenes by using hydrogen peroxide

A novel and general biomimetic non-heme Fe-catalyzed asymmetric epoxidation of aromatic alkenes by using hydrogen peroxide is reported herein. The catalyst consists of ferric chloride hexahydrate (FeCl3·OH 2O), pyridine-2,6-dicarboxylic acid (H2-(pydic)), and readily accessible chiral N-arenesulfonyl-N′-benzyl-substituted ethylenediamine ligands. The asymmetric epoxidation of styrenes with this system gave high conversions but poor enantiomeric excesses (ee), whereas larger alkenes gave high conversions and ee values. For the epoxidation of trans-stilbene (1a), the ligands (S,S)-N-(4-toluenesulfonyl)-1,2- diphenylethylenediamine ((S,S)-4a) and its N′-benzylated derivative ((S,S)-5a) gave opposite enantiomers of trans-stilbene oxide, that is, (S,S)-2a and (R,R)-2a, respectively. The enantioselectivity of alkene epoxidation is controlled by steric and electronic factors, although steric effects are more dominant. Preliminary mechanistic studies suggest the in situ formation of several chiral Fe-complexes, such as [FeCl(L*)2-(pydic)] ·HCl (L* = (S,S)-4a or (S,S)-5a in the catalyst mixture), which were identified by ESIMS. A UV/Vis study of the catalyst mixture, which consisted of FeCl3·6H2O, H2(pydic), and (S,S)-4a, suggested the formation of a new species with an absorbance peak at λ = 465 nm upon treatment with hydrogen peroxide. With the aid of two independent spin traps, we could confirm by EPR spectroscopy that the reaction proceeds via radical intermediates. Kinetic studies with deuterated styrenes showed inverse secondary kinetic isotope effects, with values of k H/kD = 0.93 for the β carbon and kH/k D=0.97 for the a carbon, which suggested an unsymmetrical transition state with stepwise O transfer. Competitive epoxidation of para-substituted styrenes revealed a linear dual-parameter Hammett plot with a slope of 1.00. Under standard conditions, epoxidation of la in the presence of ten equivalents of H218O resulted in an absence of the isotopic label in (S,S)-2a. A positive non-linear effect was observed during the epoxidation of la in the presence of (S,S)-5a and (R,R)-5a.

A materials approach to site-isolation of grubbs catalysts from incompatible solvents and m-chloroperoxybenzoic acid

The development of a method for site-isolation of Grubbs second-generation catalyst from MCPBA is described. In these reactions, Grubbs catalyst was dissolved in a solvent consisting of a mixture (1:1 v/v) of 1-butyl-3- methylimidazolium hexafluorophosphate and methylene chloride and completely encapsulated within a thimble fabricated from polydimethylsiloxane (PDMS). A series of molecules that react by cross metathesis or ring-closing metathesis were added to the interior of the thimble and allowed to react. In the last step, m-chloroperoxybenzoic acid (MCPBA) dissolved in MeOH/H2O (1:1 v/v) was added to the exterior of the PDMS thimble. Small organic molecules diffused through the PDMS to react with MCPBA to form epoxides, but the Grubbs catalyst remained encapsulated. This result is important because Grubbs catalyst catalytically decomposes MCPBA at ratios of MCPBA to Grubbs of 3000 to 1. The yields for this two-step cascade sequence ranged from 67 to 83%. The concept behind this sequence is that small organic molecules have high flux through PDMS but large molecules - such as Grubbs catalyst - and ionic reagents-such as MCPBA-have much lower flux through PDMS. Small molecules can thus react both outside and inside PDMS thimbles, whereas incompatible catalysts and reagents remain site-isolated from each other. This method does not require alteration of structures of the catalysts or reagents, so it may be applied to a wide range of homogeneous catalysts and reagents. To demonstrate further that the catalyst was encapsulated, the Grubbs catalyst was successfully recycled within the cascade sequence.

Iron-catalyzed asymmetric epoxidation of aromatic alkenes using hydrogen peroxide

(Chemical Equation Presented) Ironing out the wrinkles: Highly enantioselective catalytic asymmetric epoxidation of aromatic alkenes with hydrogen peroxide proceeds smoothly in the presence of a catalyst system consisting of ferric hexahydrate, pyridine-2,6-dicarboxylic acid, and the novel chiral ligand 1 in 2-methylbutane-2-ol solvent at room temperature within 1 h (see scheme; Bn = benzyl).

Generation of Sulfur Ylides from Sulfonium Salts and Their Reactions. Comparative Study of Electrochemical Reduction with the Base Method and Mechanism Elucidation by the MO Method

The cathodic reduction of sulfonium salts in acetonitrile in the presence and absence of benzaldehyde was carried out. Results were compared with results of the base method. In the presence of benzaldehyde, the electrochemical reduction gave epoxides as a result of the Corey-Chaykovsky reaction, thus confirming ylide formation. The electrochemical reduction of sulfonium salts without benzaldehyde yielded rearrangement products in high yield. On the contrary, upon base treatment of sulfonium salts without benzaldehyde, symmetrical epoxides derived from the benzyl group of the sulfonium salt are obtained as main products as a result of the auto oxidation of the sulfur ylide. The reaction mechanisms were elucidated based on the results obtained by a semi-empirical molecular orbital method.

A novel epoxidation reaction of olefins using a combination of chloramine-M, benzaldehyde, and benzyltriethylammonium chloride

A combination of Chloramine-M (CH3SO2NClNa), benzaldehyde, and benzyltriethylammonium chloride (BTEAC) was found to epoxidize a wide range of olefins. While epoxidation of trans-olefins provided exclusively trans- epoxides, cis-olefins (cis-stilbene, cis-β-methylstyrene, and 4-cis-octene) gave trans-epoxides as major products. Good to excellent diastereoselectivities were obtained for epoxidation of two substituted cyclohexenes. Chloramine-T was found to give a slower reaction than Chloramine-M. cis-N-Sulfonyloxaziridine D is proposed to be the epoxidizing agent in this novel epoxidation reaction on the basis of the mechanistic studies.

One-pot conversion of α-substituted arylacetaldehydes into α-dicarbonyl compounds

α-dicarbonyl compounds 7-12 can be easily prepared by reaction of methylene chloride solutions of several α-substituted arylacetaldehydes 1-6 with a slight excess of tris-(o,p-dibromophenyl) ammoniumyl hexachloro antimonate A.

Photoinduced Electron Transfer Reaction. Part 3. 9,10-Dicyanoanthracene-sensitized Photo-oxidation of Electron-rich Stilbene Oxides

The 9,10-dicyanoanthracene (DCA)-sentisized photo-oxygenation of the electron-rich stilbene oxides (1) gives the ozonides (2) almost quantitatively.The fluorescence of DCA is quenched by (1) at a diffusion-controlled rate and the above reaction is quenched by polymethoxybenzenes which indicates that an electron transfer mechanism is involved.The quantum yield for ozonide formation varies from 0.6 for trans-2-(4-methoxyphenyl)-3-phenyloxirane (1d) to 2.4 for trans-2,3-bis(4-methoxyphenyl)-2,3-diethyloxirane (1h), suggesting a duplex reaction mechanism such as photo-oxygenation by superoxide and a Barton mechanism after the initial electron transfer from the epoxides (1) to the excited singlet state of DCA.