O. A. Shumova

Alkylation of phenol by β-pinene in the presence of aluminum phenolate

The alkylation of phenol by β-pinene using Al(OPh)3 as a catalyst was studied. It was found that the composition of the products depended on the ratio of starting materials. The principal products were chromane-type ethers with an equimolar ratio of starting materials and an excess of phenol. ortho-Alkylated phenol and an ether with a terpene substituent of bornyl structure were formed with a two-fold excess of β-pinene.

Alkylation of p-cresol with camphene in the presence of aluminum-containing catalysts

Alkylation of p-cresol with camphene was studied in the presence of aluminum-based catalysts (i-PrO)3Al, AlH3, AlCl3, (i-Bu)2AlH, EtAlCl2, and LiAlH4. Aluminum isopropylate was a selective catalyst for the preparation of ortho-isobornylphenol, its activity being close to that of aluminum phenolate.

New sulfur-containing antioxidants based on 2,6-diisobornylphenol

New sulfur-containing isobornylphenols were synthesized and their antioxidant and membrane protective activities were studied.

Synthesis of phenolic antioxidants with isobornyl and tert-butyl fragments

Hybrid antioxidants, phenols with a terpene and tert-butyl substituents, were synthesized by the alkylation of 2-tert-butyl-4-methylphenol with camphene and 2-isobornylphenol with tert-butyl chloride in the presence of acidic heterogeneous catalysts, montmorillonite KSF and FIBAN K-1. Antioxidant activity of the synthesized terpenophenols was evaluated using spectrophotometry.

Aluminum phenoxide-promoted alkylation of phenol with α- and β-pinenes

Alkylation of phenol with natural α- and β-pinenes in the presence of Al(OPh)3 gives the O- and C-alkylation products with the structurally different terpene fragments. The terpenophenols obtained have proved to be optically active.

Synthesis and properties of ω-(hydroxyaryl)alkylsulfides based on 2-isobornyl-6-methyl-4-propylphenol

Proceeding from 2-isobornyl-6-methyl-4-propylphenol new derivatives have been synthesized having sulfur atoms included in different functional groups. Antiradical and antioxidant activity, as well as membrane-protecting properties of the derivatives of 2-isobornyl-6-methyl-4-propylphenol in chemical and biological model systems have been investigated.

o-Bornylphenol: Stereochemistry and synthesis of new derivatives from its (+)-enantiomer

New derivatives of the (+)-enantiomer of o-bornylphenol were synthesized with a view to determine the configuration of chiral centers therein. The absolute configuration of the terpene substituents in the Mannich reaction product obtained from 4,13-diaza-18-crown-6 was estimated as (1R,2R,4S) on the basis of anomalous X-ray scattering.

Rearrangement of Bornyl Phenyl Ether

We previously studied rearrangement of isobornyl phenyl ether under catalysis by acids and aluminum phenoxide [1]. Comparison of the experimental data obtained in the reaction catalyzed by acids and in the presence of aluminum phenoxide led us to presume that in the first case the rearrangement follows mainly intermolecular mechanism, and in the second, intramolecular. As a result, high regioand stereoselectivity of the process were rationalized by tandem Claisen and Wagner–Meerwein rearrangements occurring intramolecularly in the initially formed aluminum complex with isobornyl phenyl ether [1].