Umsetzungen des Cyclohex‐3‐en‐carbaldehyd‐p‐toluolsulfonylhydrazons

The vacuum thermolysis (80–90°) of the sodium salt of cyclohex‐3‐ene‐carbaldehyde p‐toluenesulfonylhydrazone (1) 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 3:1), 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 1‐methylcyclohexa‐1, 3‐diene (9) and bicyclo [4.1.0]hept‐3‐ene (8). Under protic conditions (in ethylene‐glycol) methylenecyclohex‐3‐ene, 1‐methylcyclohexa‐1, 3‐diene and 1‐methylcyclohexa‐1, 4‐diene (14) were produced in a ratio of 1:1:1. The direct mild thermolysis of cyclohex‐3‐ene‐carbaldehyde p‐toluenesulfonylhydrazone (1) in benzene solution afforded N‐(p‐toluenesulfinyl)‐O‐(p‐toluenesulfinyl)‐cyclohex‐3‐en‐yl‐α‐methanolamine (15) and di‐(cyclohex‐3‐en‐yl‐methyl)‐ammonium p‐toluenesulfonate (16), the structures of which were supported by their nmr. spectra and by alkaline cleavage.