The vacuum thermolysis (80-90") of the sodium salt of cyclohex-3-ene-carbaldehyde p-toluenesulfonylhydrazone (I) in silicone oil gave diazomethyl-cyclohex-3-ene ( 2 ) . Pyrolytic and photolytic decomposition of this diazo compound 2 lead to methylenecyclohex-3-ene (5) and bicyclo[4.1.0]hept-2-ene (6) (about 3: l), while the CuCl catalyzed cleavage yielded only 5. The postulated carbene mechanism should also apply under the direct aprotic decomposition conditions of the sodium salt of 1 in diglyme, where methylenecyclohex-3-ene and bicyclo[4.1.0]hept-2-ene (about 3 : 1) were formed besides small amounts of l-methylcyclohexa-l,3-diene (9) and bicyclo[il.l .O]hept-3-ene (8). Under protic conditions (in ethylene-glycol) methylenecyclohex-3-ene, l-methylcyclohexa-l,3-diene and l-methylcyclohexa-l,4-diene (14) were produced in a ratio of 1 : l : l .
The direct mild thermolysis of cyclohex-3-ene-carbaldehyde p-toluenesulfonylhydrazone (1) in benzene solution afforded N-(p-toluenesulfonyl)-O-(p-toluenesulfinyl)-cyclohex-3-en-yl-ccmethanolamine (15) and di-(cyclohex-3-en-yl-methyl)-amnionium p-toluenesulfonate (16), the structures of which were supported by their nmr. spectra and by alkaline cleavage.