2.4- Dimethoxy-3-methyl-phenol

Phenol, 2,4-dimethyl- 2,4-xylenol Phenol, 3,5-dimethyl- 3,5-xylenol Phenol, 2-dimethoxy- guaiacol Phenol, 2-methyl- o-cresol Phenol, 3-methyl- m-cresol Phenol, 4-methyl- /7-cresol Phenol. 2,4,6-trimethyl- mesitol ... 

FIGURE 10.12 Pyrogram of oak wood pyrolyzed at 600°C. Peaks 1 = acetic acid, 2 = furan carboxaldehyde, 3 = 2-methoxy -methyl phenol, 4 = 2,6-dimethoxy phenol, 5 = 2,6-dimethoxy-4-propenyl phenol. 

The BBrs reaction with 1. l-dimethoxy-2.4.6-di-tert-butyl-4-(4 -methoxyphenyl)-X -phosphorin 200 leads to cleavage of both methoxy groups in addition to the methoxy group at the phosphorus, the 4 -methoxy group is attacked. The 2-hydro-4-(4 -hydroxyphenyl)-phosphinic acid methyl ester 201 can be methylated with methyl iodide in methanol/sodium methylate at the phenolic group, leading to 202, which can also be prepared by hydrogen peroxide oxidation of 2.6-di-tert-butyl-4-(4 -methoxy phenyl)-X -phosphorin 204 to 203, followed by diazomethane methylation (see Table 13, p. 61). 

Dimethoxyfuran is readily available from the enolic dimethyl 3,4-dihydroxyfuran-2,5-dicarboxylate. This intermediate, like a phenol, can be readily O-methylated or O-benzy-lated. Hydrolysis and decarboxylation then furnishes the 3,4-dialkoxy compounds (78HCA430). The dimethoxy compound readily enters into Diels-Alder reactions, the Man-nich reaction, and may be lithiated. On mild acid hydrolysis it supplies, in poor yield, 4-methoxyfuran-3(2/f)-one and not tetrahydrofuran-3,4-dione, which is not produced by attempted hydrogenolysis of 3,4-dibenzyloxyfuran either. The dione, however, is known, and surprisingly exists in the diketo form (60JA3219). 

A 31.0 g sample of l-allyloxy-2,4-dimethoxybenzene was gently heated with a soft flame until the internal temperature reached 215 °C. An exothermic reaction took place, with the temperature rising to 270 °C. The residue left in the flask was largely 2-allyl-4,6-dimethoxy phenol, that contained perhaps 10% of 2,4-dimethoxyphenol which resulted from the pyrolytic loss of the allyl group. This mixture was methylated without further purification. 

The biosynthetic work on mescaline in the peyote cactus L. williamsii and in the Peruvian cactus T. pachanoi has led to the formulation of biosynthetic pathways according to Scheme 2. A major pathway probably involves decarboxylation of tyrosine followed by hydroxylation to yield dopamine. Dopamine is methylated on the meta hydroxy group to 4-hydroxy-3-methoxyphenethylamine (3-methoxytyramine) which then undergoes hydroxylation to the key intermediate 4,5-dihydroxy-3-methoxyphenethylamine (20). Para-O-methylation of 20 yields 3,4-dimethoxy-5-hydroxyphenethylamine (21), which is the immediate precursor of the main phenolic tetrahydroisoquinolines of peyote. Alternatively, meta-O-methylation yields 3,5-dimethoxy-4-hydroxyphenethylamine (19), which is further efficiently methylated to mescaline. Parallel pathways involving N-methylated compounds probably exist in these cacti (10). 

Dimethoxy Phenol 3,4-Dimethyl 1,2-Cyclopen tandione 5-Ethyl 3-Hydroxy 4-Methyl 2(5H)-Furanone 3-Ethyl Pyridine Furfuryl Mercaptan Geranyl Isovalerate 2,3 -Heptandione (Z)-3-Hexenyl Butyrate (Z)-3-Hexenyl Formate Hexyl Butyrate Hexyl Hexanoate Isoamyl Isobutyrate Isobutyl Formate Isobutyl Hexanoate Linalool Oxide... 

On heating with alkali, the side chain was eliminated, leaving an optically inactive phenol w hich on methylation yielded 4,8-dimethoxy-... 

The reaction of 3,4-dimethoxyfuran with 2,3-diphenylcyclopropenone in refluxing toluene gave 2,3-dimethoxy-5,6-diphenylphenol (6 a) in 24% yield. Similarly, the reaction of 3,4-dimethoxyfuran with 2-methyl-3-phenylcyclopropenone produced 2,3-dimethoxy-5-methyl-6-phenylphenol (6b) in 9% yield. These phenols probably arise via the Diels-Alder 1 1 addition products followed by decarbonylation and rearrangement. The yields of these phenols were greatly improved to 51 and 69%, respectively, by applying 8-10 kbar to the reaction mixtures. ... 

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