6652-29-5

Upstream product

• 139-02-6 sodium phenoxide 
• 447-31-4 Desyl chloride 
• 108-95-2 phenol 
• 134-81-6 benzil 
• 1484-50-0 desyl bromide 
• 93-89-0 benzoic acid ethyl ester 
• 946-80-5 (benzyloxy)benzene 
• 119-53-9 2-hydroxy-2-phenylacetophenone 
• 28899-97-0 triphenylbismuth(V) diacetate 

Downstream Products

• 451-40-1 phenyl benzyl ketone 
• 519-73-3 triphenylmethane 
• 596-30-5 ditrityl peroxide 
• 108-95-2 phenol 
• 602-15-3 9,10-diphenylphenanthrene 
• 3469-15-6 Diphenylketene dimer 
• 13054-95-0 2,3-diphenylbenzofuran 
• 5543-98-6 2-(4-hydroxyphenyl)-1,2-diphenyl-ethan-1-one 
• 90421-45-7 2-(2,3-Diphenyl-benzofuran-5-yl)-1,2-diphenyl-ethanone 
• 93-99-2 benzoic acid phenyl ester 
• 100-52-7 benzaldehyde 
• 134-81-6 benzil 
• 93-59-4 Perbenzoic acid 
• 106898-33-3 E-Benzoinphenylether-(p-chlorbenzoyl)phenylhydrazon 

Relevant academic research and scientific papers

Aldol-Tishchenko Reaction of α-Oxy Ketones: Diastereoselective Synthesis of 1,2,3-Triol Derivatives

α-Oxy ketones, easily accessible by conventional routes, can be selectively deprotonated generating an enolate intermediate, which upon treatment with paraformaldehyde undergoes an aldol-Tishchenko reaction, leading to relevant 1,2,3-triol fragments in a totally diastereoselective manner. The excellent stereocontrol in the generation of a quaternary stereocenter is attributed to stereoelectronic effects in the Evans intermediate. This methodology allows overcoming some limitations of our previously reported strategy, based on the reaction of α-lithiobenzyl ethers with esters and paraformaldehyde, broadening the scope of the obtained polyols. Synthetic applications of this process include the preparation of a new dilignol model and some functionalized oxetanes.

Merging α-Lithiation and Aldol-Tishchenko Reaction to Construct Polyols from Benzyl Ethers

α-Lithiobenzyl ethers, generated by selective α-lithiation, undergo an aldol-Tishchenko reaction upon treatment with carboxylic esters and paraformaldehyde. The reaction of the organolithium with the carboxylate generates an intermediate enolate that, after formaldehyde addition, affords 1,2,3-triol derivatives in a straightforward and one-pot manner. These products are obtained as single diastereoisomers bearing a quaternary stereocenter. The complete diastereocontrol of the aldol-Tishchenko process is attributed to stereoelectronic preferences in the transition state.

Cobalt-Catalyzed Reductive C-O Bond Cleavage of Lignin β-O-4 Ketone Models via in Situ Generation of the Cobalt-Boryl Species

An efficient and mild method for reductive C-O bond cleavage of lignin β-O-4 ketone models was developed to afford the corresponding ketones and phenols with PDI-CoCl2 as the precatalyst and diboron reagent as the reductant. The synthetic utility of the methodology was demonstrated by depolymerization of a polymeric model and gram-scale transformation. Mechanistic studies suggested that this transformation involves steps of carbonyl insertion, 1,2-Brook type rearrangement, β-oxygen elimination, and rate-limiting regeneration of the catalytic active Co-B species.

Synthesis of benzofurans from the cyclodehydration of α-phenoxy ketones mediated by Eaton’s reagent

Cyclodehydration of α-phenoxy ketones promoted by Eaton’s reagent (phosphorus pentoxide–methanesulfonic acid) is used to prepare 3-substituted or 2,3-disubstituted benzofurans with moderate to excellent yields under mild conditions. The method provides a facile access to benzofurans from readily available starting materials such as phenols and α-bromo ketones. The reaction is highly efficient, which is attributed to the good reactivity and fluidity of Eaton’s reagent. The reaction can be applied to prepare naphthofurans, furanocoumarins, benzothiophenes, and benzopyrans.

Exploring the Reactivity of α-Lithiated Aryl Benzyl Ethers: Inhibition of the [1,2]-Wittig Rearrangement and the Mechanistic Proposal Revisited

By carefully controlling the reaction temperature, treatment of aryl benzyl ethers with tBuLi selectively leads to α-lithiation, generating stable organolithiums that can be directly trapped with a variety of selected electrophiles, before they can undergo the expected [1,2]-Wittig rearrangement. This rearrangement has been deeply studied, both experimentally and computationally, with aryl α-lithiated benzyl ethers bearing different substituents at the aryl ring. The obtained results support the competence of a concerted anionic intramolecular addition/elimination sequence and a radical dissociation/recombination sequence for explaining the tendency of migration for aryl groups. The more favored rearrangements are found for substrates with electron-poor aryl groups that favor the anionic pathway.

α-Lithiated Aryl Benzyl Ethers: Inhibition of [1,2]-Wittig Rearrangement and Application to the Synthesis of Benzo[b]furan Derivatives

The use of t-BuLi at low temperature selectively leads to α-lithiation of benzyl phenyl ether generating a stable organolithium, which can be efficiently trapped with a variety of selected electrophiles prior to suffering the expected [1,2]-Wittig rearrangement. In the case of (o-alkynyl)phenyl benzyl ethers, the intermediate α-aryloxyorganolithium undergoes an unexpected anti intramolecular carbolithiation reaction leading to functionalized benzo[b]furan derivatives.

Transformation of aryl acyloin O-alkyl and O-phenyl derivatives to ketones

The treatment of aryl acyloin (α-hydroxyketone) O-alkyl and O-phenyl derivatives with 2-3 equiv of Zn and 1-2 equiv of NH4Cl in ethanol, refluxing for 20-120 min, gave the corresponding ketones with excellent yields. Further, α,β-epoxy ketones can be efficiently transformed to β-hydroxy ketones, and 2,2-dialkoxy-1-phenyl ketone also can be dealkoxylated to 1-phenyl ketone. Copyright Taylor & Francis Group, LLC.

The Reaction of Benzil with Grignard Reagents

Benzil reacts with Grignard reagents forming, in the first step, the 1,2-addition product (C-alkylation), but often also the 1,4-addition product (O-alkylation) and the reduction product, benzoin.The product distribution has been determined for mechanistic purposes for 16 Grignard reagents using a standard procedure.These results, and observations made using deuteriated reagents and the 5-hexenyl radical probe indicate an electron transfer (ET) mechanism for reagents having hydrogen in the β-position, while a polar mechanism is the most efficient for methyl, phenyl, benzyl and allyl Grignard reagents in the ether solution.For the ET mechanism, a six-centre transition state is suggested.Furthermore, a distinction is made between the primary cage product (O-alkyl) resulting from immediate combination of the radical pair, and the secondary cage product (C-alkyl) formed in the cage after rearrangement. 5-Hexenylmagnesium bromide yields uncyclised primary and secondary cage product, but also significant amounts of cyclised C-alkylation product formed by escape of the radicals from the cage and re-encounter after cyclisation of 5-hexenyl to cyclopentylmethyl.A recently suggested mechanism based on the existence of stable radical ion pairs is found to be unacceptable.

The Catalytic Effect of Copper Ions in the Phenylation Reaction of David and Thieffry

Several types of bifunctional molecules are smoothly phenylated by triphenylbismuth diacetate in a reaction which has an induction period, a curious solvent dependence, and the need for illumination; however, the addition of a small amount of Cu(OAc)2 removes all these limitations and accelerates greatly the reaction.