Synthesis of 5-Alkylresorcinols

Aust. J. Chem. 26,799(1973) gives a 2 step synthesis of 5-alkylresorcinols by condensation of beta-ketosulphones with 3,5-dimethoxybenzyl bromide and then reduction. Aust. J. Chem. 26,183(1973) gives a synthesis from 3,5-dimethoxy-N,N-dimeth-ylbenzylamine in 7 steps (but perhaps only 4 will reach a cpd. that can give an active THC analog). 

Aust. J. Chem. 26,799(1973) gives a 2 step synthesis of 5-alkylresorcinols by condensation of beta-ketosulphones with 3,... 

Cleaver L, Croft JA, Ritchie E, Taylor WC (1976) Chemical studies of the Proteaceae. IX. Synthesis of 5-alkylresorcinols from aliphatic precursors. Aust J Chem 29 1989-2001... 

There has been considerable activity in the synthesis of orsellinic acids in the past decade. On account of their ready decarboxylation all these procedures also give access to 5-alkylresorcinols. These routes are summarised in the scheme shown. Homologous alkyl acetoacetates (R = R = alkyl) with thallium ethoxide or sodium hydride followed by reaction with diketene (route a) afford the corresponding homologous alkyl orsellinates (ref.23). In a related method (route b) methyl orsellinate (R = Me) results from the interaction of the monoanion with the dianion of methyl acetoacetate (ref.24). 

Tyman JHP, Durrani AA (1973) A Novel Synthesis of Homologous Orsellinic Acids and 5-Alkylresorcinols. Tetrahedron Letters 73 4839... 

Dihydric phenolic lipids of the cardol type are the most abundant in plant, fungal and bacterial kingdoms. The first species in which the members of the title subclass of phenolic lipids, resorcinolic lipids, were found was Ginkgo biloba (Ginkgoaceae) [6,9,10,17]. Later, the presence of resorcinolic lipids (5-n-alk(en)ylresorcinols) was shown also in other species, first, in the Anacardiaceae [14], which is an important source of various phenolic lipids, not only of alkylresorcinols but also of alkylphenols and alkylcatechols. For example, the cashew and the processing of cashew nuts are the main source of phenolic lipids for the formaldehyde-polymer industry. Aspects of Anacardium occidentale in relation to synthesis, semi-synthesis and chemical industry have been reviewed Tyman [1,11,14] as well as a recent book [2]. 

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