Zum stoffwechsel von aromaten, II. über die muconsäurespaltung von einfachen o-diphenolen / on the metabolism of aromatic compounds, ii * the muconic acid scission of simple o-diphenols

Günther Schulz, Erich Hecker
1973 Zeitschrift für Naturforschung C - A Journal of Biosciences  
The preparation of substituted cis,cis-muconic acids by oxidative ring scission of simple o-di-phenols with peracetic acid is investigated. Scission of pyrocatechol (1) to cis,cis-muconic acid (2) gives optimal yields, if acetic acid or ethyl acetate is used as solvent and if the solution is 15-20% with respect to sulfuric acid free peracetic acid comprising a one molar excess of oxidant. Under similar conditions, 3-tosylamino-pyrocatechol yields with peracetic acid the hitherto unknown
more » ... rto unknown α-tosylamino-cis,cis-muconic caid (18). 18 may be converted to α-tosylamino-traras,trans-muconic acid (19) by means of iodine, UV light or heating. From protocatechuic acid (4) under similar conditions not β-carboxy-cis,cis-muconic acid (5) is obtained, but rather β-carboxy-mucono-lactone (6 b, γ-carboxymethyl-β-carboxy-Δα-butenolide). As yet, this lactone has been accessible only from an isomer of β-carboxy-cis,cis-muconic acid, the latter being obtainable by enzymatic scission of protocatechuic acid (4). Steric effects are responsible for both, the formation of the free cis,cis-muconic acids 2 and 18 from pyrocatechol (1) and α-tosylamino-pyrocatechol, and the formation of the γ-lactone 6 b instead of β -carboxy-cis,cis-muconic acid by scission of protocatechuic acid (4). The time course of the reactions shows that - compared to pyrocatechol (1) - a 3-tosylamino-group enhances the peracetic acid scission, whereas a 4-carboxygroup as in 4 slows it down
doi:10.1515/znc-1973-11-1206 fatcat:26wr2y2tzzgbbowbto22qmsf6e