77363-84-9Relevant academic research and scientific papers
Synthetic Studies of Fungal Metabolites: Ascofuranone and Colletochlorin D
Guthrie, Anne E.,Semple, Edward J.,Joullie, Madeleine M.
, p. 2369 - 2376 (1982)
Procedures have been developed for the synthesis of hexasubstituted aromatic rings which are present in many fungal metabolites such as ascofuranone and colletochlorin D. (3-Bromo-5-chloro-2,6-dimethoxy-p-tolyl)acetaldehyde was synthesized from orcinol in eight steps.This aldehyde was converted to 2-bromo-6-chloro-3,5-dimethoxy-4-(3-methyl-2-butenyl)toluene which was subsequently formylated to afford 3-chloro-4,6-dimetoxy-2-methyl-5-(3-methyl-2-butenyl)benzaldehyde.Although various demethylation procedures were tried, demethylation of both methoxy groups could not be accomplished.In our attempts to synthesize ascofuranone, (3-bromo-5-chloro-2,6-dimethoxy-p-tolyl)acetaldehyde was treated with isopropenylmagesium bromide to afford an unsteble allylic alcohol which was immediately subjected to the conditions of the "orthoacetate Claisen rearrangement" to give 2-bromo-6-chloro-4-3,5-dimethoxytoluene.This compound was then converted to 2-bromo-6-chloro-3,5-dimethoxy-4-toluene bromide in three steps.All attempts to carry out a Wittig reaction between this compound and 6,6-dimethyl-1,4,7-trioxaspironon-8-yl methyl ketone failed.Other coupling methods were equally unsuccesful.
