4-Alkyl-resorcinoles

Since the method as given originally leads to 4-alkyl resorcinols which do not produce an active THC, it is here modified to give the 5-alkyl isomers. The method is illustrated for 1.2-dimethyl-heptyI resorcinol which gives a much more active THC than olivetol. 

Primary alkyl phenols have been prepared by the reduction of acyl phenols 1 by the demethylation of the corresponding ethers 12 by the diazotization of the corresponding amines 3 and by the alkali fusion of sulfonates.4 Alkyl resorcinols have been prepared by the reduction of acyl resorcinols.1 5 6 Alkyl chlororesorcinols have been prepared from the corresponding acyl chlororesorcinols by reduction.7... 

Where resorcinol adhesives are not suitable, resins can be prepared from modified resorcinol [128], Characteristic of these types of resins arc those used for tyre cord adhesives, in which a pure resorcinol-formaldehyde resin is used, or alternatively, alkyl resorcinol or oil-soluble resins suitable for rubber compounding are obtained by prereaction of resorcinol with fatty acids in the presence of sulfuric acid at high temperature followed by reaction with formaldehyde. Worldwide more than 90% of resorcinol adhesives are used as cold-setting wood adhesives. The other most notable application is as tyre cord adhesives, which constitutes less than 5% of the total use. 

B. M. Malyarchuk, V. Yu. Pavlyuk, F. V. Nijger, B. G. Tarasov, and P. V. Tarabarinov. Composition for plugging flooded porous strata— contains clay, alumina cement, natural zeolite, calcined soda, polyacrylamide, alkyl resorcinol resin, pentaerythritol production waste and natural saline. Patent SU 1776764-A, 1992. 

Raidma, E. 1994. Diglycidyl ethers from oil shale alkyl resorcinols. Part 1. Initial raw phenols and the structure of reaction products. Oil Shale, 11, 241-249. 

The mass spectra and pyrolysis of alkyl resorcinols are also subject to nonquantitative correlations. 3 > Lille and Kundel reported that the mass spectra of 2, 4 and 5 alkyl (C4 or larger) resorcinols were all dominated by jS-cleavage (benzylic) ions. The pyrolysis of the 2 or 4 alkylresorcinols at 700 °C was consistent with their mass spectra however, pyrolysis of 5-alkylresorcinols gave in addition to the anticipated / -cleavage products, 5,7-dihydroxyindene or an alkenylresorcinol. The yield of the unique olefin was of the same order as the peld of the 5-methylresorcinol. The basis for this reactivity discrepancy may be the scrambling of positions in the resorcinol on electron impact. 

According to the process of this invention, optically active apoverbenone is reacted with a 5-substituted resorcinol. Examples of commonly used 5-substituted resorcinols are the 5-alkyl resorcinols such as 5-n-pentyl resorcinol, 5-(l,l-dimethylheptyl)resorcinol, 5-(l,2-dimethylheptyl)resorcinol, 5-(/i-octyl)resorcinol, and the like. Either... 

It has now been discovered that 2,6-dimethoxyphenol surprisingly is alkylated almost exclusively at the 4-position by reaction with a tertiary carbinol in the presence of an acid. Such alkylation provides a l-hydroxy-2,6-dimethoxy-4-(tertiary alkyDbenzene which can readily be converted to a 5-(tertiary alkyl)resorcinol. Such process affords high 5rields of the desired 5-(tertiary alkyl)resorcinol... starting from relatively inexpensive starting materials. 

As hereinbefore pointed out, the 5-(tertiary alkyl)resorcinols thus prepared in accordance with this invention are important intermediates in the preparation of useful drugs. For example, 5-(l,l-dimethyl-heptyl)resorcinol is utilized in the preparation of l-hydroxy-3-(l,l-dimethylheptyl)-6,6a,7,8,9,l 0,10a-hexahydro-6,6-dimethyl-9H-dibenzo[b,d]pyran-9-one, which compound is extremely useful in the treatment of depression in humans, as described in U.S. Pat. Nos. 3,928,598, 3,944,673, and 3,953,603. Similarly, 5-(l,l-dimethyl-heptyl)resorcinol is required in the synthesis of3-(l,l-dimethylheptyl)-6a,7,8,9,10,10a-hexahydro-6,6-dimethyl-6H-dibenzo[b,d]pyran-l,9-diol, which compound is useful as a blood-pressure lowering agent. It can thus be seen that a commercially feasible process for preparing 5-(tertiary alkyl)resorcinols in high yield is desirable. 

Travis, C.A. Alkylated Resorcinol Derivatives for the Treatment of Immune Diseases 2001 US 6,274,635... 

Alkyl Resorcinols from Acyl Resorcinols CA 72,66922(1970) Compounds I-III may be able to give active THC analogs if used in place of olivetol for synthesis. 

Highly unsaturated alkyl resorcinols and a phloroglucinol have been found in certain... 

In a series of alkylated resorcinols the length of the alkyl chain is directly proportional to the antibacterial activity,... 

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