Tosylhydrazones hydrogen compounds

The lithium salt of an active hydrogen compound adds to the lithium salt of the tosylhydrazone of an aldehyde to give product 49, If X = CN, SPh, or S02R, 49 spontaneously loses N2 and LiX to give the alkene 50. The entire process is done in one reaction... 

In the case of sodium 2-(diarylmethylene)cyclopentanone tosylhydrazones 3, however, thermolysis gives the 3//-1,2-benzodiazepines 6 in good yield selected examples are shown. It is suggested that steric constraints in the diazo compounds 4 favor the [1,7] ring closure. The reaction proceeds by way of the intermediates 5, which rearrange to the products by a [1,5] shift of hydrogen.115... 

Recently on thermolysis or photolysis of tosylhydrazone 39 a mixture of 40 and 41 was obtained, 42 being a possible intermediate. When 41 was boiled in DMF, 40 was formed 40 could be reduced by sodium hydrogen sulfite to reform compound 41.33... 

Tosylhydrazones of aliphatic aldehydes and ketones react with a base in an aprotic solvent at 90-180 C to give diazo compounds which undergo thermal decomposition with loss of nitrogen to yield alkenes derived from hydrogen migration and cyclopropanes from intramolecular insertion. In proton donor solvents decomposition of y-tosylhydrazones by base occurs primarily by a cationic mechanism involving diazonium and/or carbenium ion intermediates. 

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