CAREER: New Applications for Ortho-Quinone Methides …


The facility with which the aromatic ring of phenols and phenol ethers undergoes electrophilic substitution has been noted. Two examples are shown in the following diagram. The first shows the Friedel-Crafts synthesis of the food preservative BHT from para-cresol. The second reaction is interesting in that it further demonstrates the delocalization of charge that occurs in the phenolate anion. Carbon dioxide is a weak electrophile and normally does not react with aromatic compounds; however, the negative charge concentration on the phenolate ring enables the carboxylation reaction shown in the second step. The sodium salt of salicylic acid is the major ptoduct, and the preference for ortho substitution may reflect the influence of the sodium cation. This is called the Kolbe-Schmidt reaction, and it has served in the preparation of aspirin, as the last step illustrates.

4-Cyanomethyl-ortho-quinone tautomerism and the …

The Domestication of ortho-Quinone Methides - …

Diels-Alder Trapping of ortho-Quinone Methides

N2 - Ortho-quinone methides are important synthetic intermediates and widely implicated in biological processes. In this Synopsis, recent advances concerning the synthesis and utility of these intermediates are discussed with a particular emphasis on metal-catalyzed formation of quinone methide intermediates. Additionally, applications of these intermediates as partners in asymmetric synthesis will be discussed including methods we have developed that involve the enantioselective Pd-catalyzed formation of ortho-quinone methides and the trapping of aforementioned intermediates with diverse nucleophiles.

The aerobic oxidation toward a transient ortho-quinone methide ..

AB - Ortho-quinone methides are important synthetic intermediates and widely implicated in biological processes. In this Synopsis, recent advances concerning the synthesis and utility of these intermediates are discussed with a particular emphasis on metal-catalyzed formation of quinone methide intermediates. Additionally, applications of these intermediates as partners in asymmetric synthesis will be discussed including methods we have developed that involve the enantioselective Pd-catalyzed formation of ortho-quinone methides and the trapping of aforementioned intermediates with diverse nucleophiles.

Diels-Alder Trapping of ortho-Quinone Methides. A New Entry to Substituted Xanthene-1,4-diones
TY - JOUR. T1 - Applications of ortho-quinone methide intermediates in catalysis and asymmetric synthesis. AU - Pathak,Tejas P. AU - Sigman,Matthew S.

Diels–Alder reaction - Wikipedia

New Methodology For The Generation Of Ortho-quinone Methides: Application To The Synthesis Of Cannabinoids.

A quinone methide is a type of conjugated ..

Sep 12, 2016 · A Catalyst-Controlled Aerobic Coupling of ortho-Quinones and Phenols Applied to the Synthesis of ..

Quinone methides can be produced in ..