20498-67-3

Upstream product

• 24845-40-7 2-(4-methoxyphenyl)acetophenone 
• 64-17-5 ethanol 
• 31179-52-9 p-anisylmagnesium bromide 
• 100-52-7 benzaldehyde 
• 18255-07-7 1-methoxy-4-<(phenylseleno)methyl>benzene 
• 100-42-5 styrene 
• 21502-70-5 tris(p-anisyl)antimony 
• 104-01-8 4-Methoxyphenylacetic acid 
• 99931-94-9 2-(4-methoxyphenyl)-1-morpholinoethan-1-one 
• 96-09-3 styrene oxide 
• 696-62-8 para-iodoanisole 
• 17988-20-4 (4-methoxy-benzyl)-trimethyl-silane 
• 5814-81-3 trans-(2R,3R)-2-phenyl-3-(4-(trifluoromethoxy)phenyl)oxirane 
• 1657-53-0 cis-4-methoxystilbene 

Downstream Products

• 1694-19-5 E-1-(phenyl)-2-(4'-methoxyphenyl)ethene 
• 127066-47-1 1-methoxy-2-(p-methoxyphenyl)-1-phenylethane 
• 1016896-31-3 (R)-1-acetoxy-1-phenyl-2-(4-methoxyphenyl)ethane 
• 1422191-20-5 (S)-1-butyryloxy-1-phenyl-2-(4-methoxylphenyl)ethane 

Relevant academic research and scientific papers

Cobalt Catalyst Determines Regioselectivity in Ring Opening of Epoxides with Aryl Halides

Ring-opening of epoxides furnishing either linear or branched products belongs to the group of classic transformations in organic synthesis. However, the regioselective cross-electrophile coupling of aryl epoxides with aryl halides still represents a key challenge. Herein, we report that the vitamin B12/Ni dual-catalytic system allows for the selective synthesis of linear products under blue-light irradiation, thus complementing methodologies that give access to branched alcohols. Experimental and theoretical studies corroborate the proposed mechanism involving alkylcobalamin as an intermediate in this reaction.

Heterogeneous visible-light-induced Meerwein hydration reaction of alkenes in water using mpg-C3N4 as a recyclable photocatalyst

A green and efficient visible light induced Meerwein hydration reaction of alkenes in aqueous medium using mpg-C3N4 as a recyclabe photocatalyst has been disclosed. This protocol provides a direct approach for the preparation of racemic alcohols via a free radical mechanism. Water acted as both a solvent and a reagent without any additives or co-solvents. The metal-free heterogeneous semiconductor is found to be fully recyclable at least 5 times without any significant reduction in activity. The Meerwein hydration reaction has an excellent substrate scope and gave the desired products in moderate to high yields. Furthermore, this reaction could be carried out under solar light irradiation and is applicable for large-scale reactions with satisfactory results.

Enantioselective 1,2-Anionotropic Rearrangement of Acylsilane through a Bisguanidinium Silicate Ion Pair

Highly enantioselective bisguanidinium-catalyzed tandem rearrangements of acylsilanes are reported. The acylsilanes were activated via an addition of fluoride on the silicon to form a penta-coordinate anionic silicate intermediate. The silicate then underwent alkyl or aryl group migration from the silicon atom to the neighboring carbonyl carbon atom (1,2-anionotropic rearrangement), followed by [1,2]-Brook rearrangement to provide the secondary alcohols in high yields with excellent enantioselectivities (up to 95% ee). The isolation of an α-silylcarbinol intermediate as well as DFT calculations revealed that the 1,2-anionotropic rearrangement occurred via a bisguanidinium silicate ion pair, which is the stereodetermining step. The chiral center formed is then retained without inversion through the subsequent [1,2]-Brook rearrangement. Crotyl acylsilanes were smoothly transformed into homoallylic linear crotyl alcohols with retention of E/Z geometry, and no branched alcohols were detected. This clearly suggested that the 1,2-anionotropic rearrangement occurred through a three-membered instead of a five-membered transition state.

A practical method to stereospecifically synthesize trans-stilbene derivatives

A practical method to stereospecifically synthesize trans-stilbenes was developed via the one-pot benzylation-dehydration reaction of aromatic aldehydes with benzyltrimethylsilane (BTMS), which was driven by tetrabutylammonium fluoride (TBAF) in THF. At the same time a plausible description of the whole process was proposed and the effects of substituted groups on the reaction were investigated. Also this method was employed to synthesize three precursors of natural products with excellent yields, which demonstrated that this method is much efficient and practical in the synthesis of some natural products. A practical method to stereospecifically synthesize trans-stilbenes was developed via the one-pot benzylation-dehydration reaction of aromatic aldehydes with benzyltrimethylsilane, which was driven by tetrabutylammonium fluoride in THF. A plausible description of the whole process was proposed and the effects of substituted groups on the reaction were investigated. This method was employed to synthesize three precursors of natural products with excellent yields. Copyright

1,2-Diarylethanols by alternative regioselective reductive ring-opening of 2,3-diaryloxiranes

Non-symmetrical ￡rans-2,3-diaryloxiranes have been regioselectively opened by catalytic hydrogenation over Pd/C, NaBH4/Pd and [Cp 2TiCl]/H2O. Although in the catalytic hydrogenation reactions the epoxides were mainly opened at the β-carbon with respect to the substituted aryl ring in all cases, with the [Cp2TiCl]/H 2O system the regioselectivity was affected by the electronic properties of the aryl residues, the epoxides being opened on the carbon bearing the most electron-releasing or the least electron-withdrawing group. With the NaBH4/Pd system different regioisomers were obtained depending on the substituents. Starting from enantioenriched epoxides, no loss of optical purity was observed in the alcohols formed.

Regioselectivity of the rhodium-catalyzed hydroboration of vinyl arenes: Electronic twists and mechanistic shifts

Any substituent does it: The hydroboration of vinyl arenes with pinacol borane (HBPin) and cationic rhodium complexes selectively placed the boron proximal to the aryl rather than phenyl ring, regardless of whether this ring bears electron-donating or electron-withdrawing substituents. In competition experiments between styrene and various vinyl arenes, preferential hydroboration also occured at the substituted arene (see scheme). Hammett plots indicate a break in the mechanism. (Chemical Equation Presented).

Couplings of benzylic halides mediated by titanocene chloride: Synthesis of bibenzyl derivatives

Titanocene monochloride catalyzes the homocoupling of benzylic halides and benzylic gem-dibromides to give the corresponding bibenzyl and stilbenyl systems. Exposure of benzylic bromides to Ti(III) in the presence of aldehydes gave rise to the Barbier-type products. Examples of the utility of the herein described processes are included.

Silver catalyzed zinc Barbier reaction of benzylic halides in water

Benzylic chlorides react in aqueous dibasic potassium phosphate under silver catalysis with aromatic aldehydes in the presence of zinc dust to give 1,2-diaryl alcohols in moderate to good yields. Dimerization to bibenzyls and reduction of the halide are important side reactions. A wide range of substituted aromatic and heteroaromatic aldehydes and of substituted benzylic chlorides can be used. Aliphatic aldehydes and ketones are unreactive. A mechanism of two SET on the metal surface is discussed.

Photochemically induced coupling reaction of triarylstibines with olefins

Photoreaction of triarylstibines with styrenes resulted in the formation of 2-aryl-1-phenylethanols accompanied by air oxidation. Formation of the products has been explained by the valence expansion of the oxygen-antimony- styrene complex to a five-valent intermediate, followed by reductive coupling.

Side-chain fragmentation of arylalkanol radical cations. Carbon-carbon and carbon-hydrogen bond cleavage and the role of α- and β-OH groups

A product analysis and kinetic study of the one-electron oxidation of a number of 1-arylpropanols, 1,2-diarylethanols, and some of their methyl ethers by potassium 12-tungstocobaltate(III) (abbreviated as Co(III)W) in aqueous acetic acid was carried out and complemented by pulse radiolysis experiments. The oxidations occur via radical cations which undergo side-chain fragmentation involving the C(α)-H and/or C(α)-C(β) bond. With 1-(4-methoxyphenyl)-2-methoxypropane (1), only deprotonation of the radical cation is observed. In contrast, removing the ring methoxy group leads to exclusive C-C bond cleavage in the radical cation. Replacing the side-chain β-OMe by β-OH, the radical cation undergoes both C-C and C-H bond cleavage, with both pathways being base catalyzed. C-C bond breaking in the radical cation is also enhanced by an α-OH group, as shown by 1-(4-methoxyphenyl)-2,2-dimethyl-1-propanol (7), where this pathway, which is also base catalyzed, is the only one observed. Interestingly, α- and β-OH groups exhibit a very similar efficiency in assisting the C-C bond cleavage route in the radical cations, as is evident from the kinetic and products study of the oxidation of 1-phenyl-2-(4-methoxyphenyl)ethanol (5) and 1-(4-methoxyphenyl)-2-phenylethanol (6) by Co(III)W, and from pulse radiolysis experiments on 5 and 6. C-C bond cleavage is the main reaction for both radical cations which exhibit a very similar rate of fragmentation (k = 2.0 and 3.2 x 104 s-1, respectively). In both fragmentation reactions a small solvent isotope effect, k(H2O)/k(D2O) (1.4 for 5.+ and 1.2 for 6.+) and negative activation entropies are observed. These data suggest that a key role in the assistance by α- or β-OH groups to C-C bond cleavage is played by hydrogen bonding or specific solvation of these groups. The kinetic study of the oxidations promoted by Co(III)W has also shown that when only one group, OH or OMe, is present in the side chain (either on C(α) or C(β)), the fragmentation step or both the electron transfer and fragmentation steps contribute to the overall oxidation rate. However, with an OH group on both carbons of the scissile bond, as in 1-(4-methoxyphenyl)-1,2-propanediol (9), the rate of C-C bond cleavage is so fast that the electron transfer step becomes rate determining.