Lactone tosylhydrazone salts

Pyrolysis of lactone tosylhydrazone salts. Agosta et al.3 have developed a process that is formally a reversal of the Baeyer-Villiger oxidation, that is, a method for conversion of lactones into cyclic ketones. An example is the synthesis of the spiro[3.4]-octane-l-one (5). The starting material is the lactone (1) this is converted into the... 

Thermal decomposition of y-lactone tosylhydrazone sodium salts are reported to yield cyclobu-tanones, which can be accounted for by rearrangement of an intermediate oxycarbene. In this manner, the sodium salts of dihydrofuran-2(37/)-one tosylhydrazones 1 were decomposed as a loose powder, at 310 C in a bulb-to-bulb distillation apparatus at an initial pressure of 0.1 Torr, to give the corresponding cyclobutanones 2 in addition to enol ethers, cyclopropanes and open-chain alkenes. Condensable products (74-76%) were collected at — 78 °C, weighed and the ratio of components was determined from their relative GC peak areas.63... 

Intramolecular carbene cycloadditions have been used in syntheses of prostanoids, diterpenoids, and other caged structures. Although unlikely to be of great synthetic use, the pyrolyses of the sodium salts of the lactone tosylhydrazones (89) give cyclopropane products via the oxycarbene intermediates as reported in preliminary form last year. ... 

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