oxime as a solid m p 114 u00b0 115 u00b0 c a mixture of the above oxime 3 7 g 18 4 mmol r 1 2 bromoethyl 3 piperidinecarboxylic acid ethyl ester hydrobromide 7 0 g 20 2 mmol ep 374801 potassium carbonate 10 2 g 73 5 mmol and acetone 150 ml was stirred at ambient temperature for 11 days the mixture was filtered and the solvent evaporated in vacuo the residue was purified by column chromatography on silica gel 200 g heptane ethyl acetate 3 2 to give 2 5 g of r 1 2 2 benzylidene cyclohexylidene amino oxy ethyl 3 piperidinecarboxylic acid ethyl ester as an oil the above ester 2 5 g 6 5 mmol was dissolved in ethanol 20 ml and 4n sodium hydroxide 4 9 ml was added the mixture was stirred at ambient temperature for 3 h and excess concentrated hydrochloric acid was added followed by dichloromethane 300 ml and water 15 ml the phases were separated and the organic phase was dried mgso 4 and the solvent evaporated in vacuo the residue was re evaporated with acetone and recrystallised from acetone 180 ml to give 1 5 g of the title compound as a solid m p 116 u00b0 c dec calculated for c 21 h 30 n 2 o 3 hcl c 63 9 h 7 9 n 7 1 found c 63 9 h 7 6 n 6 9 a mixture of 2 phenyl 1 tetralone 1 1 g 5 mmol j am chem soc 1949 71 1092 hydroxylammonium chloride 0 7 g 10 mmol and dry pyridine 30 ml was heated at reflux for 4 h and then.