17959-01-2

Upstream product

• 100-42-5 styrene 
• 95-48-7 ortho-cresol 
• 132980-50-8 2-<1-(1H-Benzotriazol-1-yl)ethyl>-6-methylphenol 
• 133349-96-9 2-<1-(1H-Benzotriazol-1-yl)ethyl>-6-methylanisole 
• 133349-94-7 2-(1H-Benzotriazol-1-ylmethyl)-6-methylanisole 
• 132980-33-7 2-(1H-Benzotriazol-1-ylmethyl)-6-methylphenol 

Downstream Products

• 120007-39-8 (Z)-5,5'-Dimethyl-3,3'-bis-(1-phenyl-ethyl)-bicyclohexylidene-2,5,2',5'-tetraene-4,4'-dione 
• 120007-42-3 5,5'-Dimethyl-3,3'-bis-(1-phenyl-ethyl)-biphenyl-4,4'-diol 

Relevant academic research and scientific papers

Hydroarylation of alkynes and alkenes through alumina-sulfuric acid catalyzed regioselective C–C bond formation

A highly atom-efficient synthetic protocol for hydroarylation of terminal-aryl alkynes and styrene through the regioselective C–C bond formation via the electrophilic addition of naphthols and substituted phenols has been developed using alumina-sulfuric acid as a heterogeneous supported solid acid catalyst. This methodology shows excellent regioselectivity and affords the desired product in good to excellent yield. The heterogeneous catalyst can also be recycled efficiently without much loss of activity.

A simple Lewis acid induced reaction of phenols with electrophiles: Synthesis of functionalized 4H-chromenes and ortho-benzylphenols

Lewis acid ZnCl2 promoted cyclization protocol to 4H-chromenes is accomplished, using readily available phenols and acetophenones as starting materials. Interestingly, the process is feasible under the solvent free environment. Synthesis of a variety of 4H-chromenes have been accomplished using this strategy. In addition, this concept is extended to the synthesis of ortho-benzylphenols by treating phenols either with styrenes or secondary benzylic alcohols.

Room Temperature Catalyst System for the Hydroarylation of Olefins

A simple protocol for the hydroarylation of olefins to yield diarylmethine products is described. A Friedel-Crafts-type synthetic strategy allows direct access to biorelevant products in high atom efficiency. A combination of substoichiometric amounts of TMSCl and ZnBr2 promotes a rapid hydroarylation process at ambient temperature. The method is high yielding and is amenable to scale-up protocols.

o-(α-Benzotriazolylalkyl)phenols: Versatile Intermediates for the Synthesis of Substituted Phenols

Phenols and naphthols are benzotriazolylmethylated by 1-(hydroxymethyl)-1H-benzotriazole (13) (a formaldehyde derivative) in the o- or (if both o-positions are occupied) in the p-position.The reaction can be extended to other aldehydes in the case of the naphthols.The methylene group in the o-(benzotriazolylmethyl)phenols can be lithiated (but only after trimethylsilyl protection of the hydroxy group) and then substituted by various electrophiles.The benzotriazole residues in both the primary products and in their substituted derivatives can be displaced by the alkylanions of Grignard reagents or by hydride ions allowing the elaboration of many new types of substituted phenols. Key Words: Lithiation/ Mannich reaction/ Alkylation/ Grignard reaction/ Condensation

N-benzotriazoles: Preparation and Use in Synthesis

Methoxybenzenes and -naphthalenes are benzotriazolylmethylated in the para-position or if this is blocked in an ortho-position.The methylene groups in the products are readily substituted by electrophiles via the lithiated derivatives.Displacement ot the benzotriazole group can be effected by organometallic reagents or by electron-rich benzoid compounds to afford a versatile method for the synthesis of substituted aryl ethers.Key Words: Lithiation/ Grignard reaction/ Condensation/ Aryl ethers/ Diarylmethanes

REACTION OF o-, m-, AND p-CRESOL WITH STYRENE IN THE PRESENCE OF ALUMINIUM CRESOLATES

The alkylation of o-, m-, and p-cresol by styrene in the presence of aluminium cresolates gives a mixture of isomeric (α-methylbenzyl)cresols, whose composition is predominated by the ortho-alkylation products. 2,6-Di(α-methylbenzyl)-4-methylphenol has been separated into a racemate and the meso form, whose ratio varies from 1:1 (130 deg C) to 2:1 (210 deg C).The erythro and threo forms of 2,6-di(α-methylbenzyl)-3-methylphenol have been recovered in ratios equal to 1:1.4 (130 deg C) and 1:1.29 (150 deg C), which point out the stereospecifity of the alkylation reaction.

REACTIVITY OF 2,4- AND 2,6-DIALKYLPHENOLS DURING SUBSTITUTION BY WEAK ELECTROPHILIC AGENTS

The 2,4- and 2,6-dialkylphenols have different reactivities during substitution by weak electrophiles. 2,4-Dialkylphenols enter readily into acid-catalyzed alkylation and condensation with aldehydes, and their reactivity is practically independent of the structure of the alkyl substituents. 2,6-Dialkylphenols have significantly lower reactivity in these reactions, while sterically hindered 2,6-dialkylphenols hardly react at all with alkenes and aldehydes under the conditions of acid catalysis.This is evidently due to weakening of the interaction between the hydroxyl group and the aromatic ring in the conjugation mechanism.