84213-07-0Relevant academic research and scientific papers
Trifluoroacetic Acid Catalysed Claisen Rearrangement of 5-Allyloxy-2-hydroxybenzoic Acid and Esters: an Efficient Synthesis of (+/-)-Mellein
Harwood, Laurence M.
, p. 1120 - 1122 (1982)
5-Allyloxy-2-hydroxybenzoic acid (1a) and the esters (1b - f) in refluxing trifluoroacetic acid are smoothly converted into 3,4-dihydro-5,8-dihydroxy-3-methylisocoumarin (3) and the corresponding 4-alkoxycarbonyl-2,3-dihydro-5-hydroxy-2-methylbenzofurans (4a - f) via regioselective Claisen rearrangement to the 6-position of the aromatic nucleus with subsequent acid catalysed cyclisation.
Access to Phenolic Fungal Metabolites via the Acid-catalysed Claisen Rearrangement. The Total Synthesis of (+/-)-Mellein, Aurocitrin, and 5',6'-Dihydroaurocitrin
Harwood, Laurence M.
, p. 2577 - 2582 (2007/10/02)
Regioselective trifluoroacetic acid catalysed rearrangement of allyl 5-allyloxy-2-hydroxybenzoate (2b) with concomitant cyclisation of the initial product permits the simple preparation of 3,4-dihydro-5,8-dihydroxy-3-methylisocoumarin (5).Hydrogenolysis of the non-hydrogen bonded hydroxy group yields (+/-)-mellein (7) whereas elaboration of the lactone moiety of compound (5) provides access to aurocitrin (8b) and its side chain analogues.
