Photochemistry without light - reaction of active oxalate esters with anthracenophanes

Certain anthracenophanes undergo photochemistry without light, sensitised by active oxalates. Although the quantum yield of sensitisation is extraordinarily high, no direct evidence for the expected radical cation intermediate has been found.     

CHEMILUMINESCENCE INVOLVING PEROXIDE DECOMPOSITIONS

Abstract— It is a reasonable assumption that many of the known cherniluminescent organic compounds react to give a carbonyl group in an excited state. By extension of this hypothesis we were led to test several substituted acridinium salts. Oxidation of these with hydrogen peroxide in the presence of base resulted in the formation of N-methylacridone in high yield, and the emission of light from an excited state of this ketone. Mechanisms for this process are discussed. Interest in indole derivatives aroused by the finding of a tryptamine residue in the luminescent cypridina luciferin, in conjunction with the hypothesis mentioned above, has led to an investigation of some indoles, and in particular, the important isolable peroxide of tetrahydrocarbazole. A preliminary account of this work is given.     

Metal catalysed light emission from a dioxetan

The photosensitised oxidation of 9- (2-adamantylidene)-N-methylacridan affords a compound whose properties are best explained by a dioxetan structure. Its decomposition is catalysed by lanthanide chelates with energy transfer.     

Total synthesis of colchicine modelled on a biogenetic theory

A five step synthesis of desacetamidocolchiceine (XLVI) is described in which rings A and C are joined by oxidative coupling of the tropolone system. This completes a biogenetic-type total synthesis of colchicine (I).     

The structure and chemistry of hirsutic acid

By a necessary combination of chemical and X-ray studies the structure and stereochemistry of the sesquiterpenoid acid, hirsutic acid C (C₁₅H₂₀O₄) from Stereum hirsutum have been established as shown in I. An unusual rearrangement involving solid state X-irradiation has been discovered and evaluated.