Catechol → 1'-ethoxycarbonyl-spiro[1,3-benzodioxole-2,4'-piperidine]

Participants

Reaction Steps

A mixture of 1-ethoxycarbonyl-4-piperidinone (17 g), pyrocatechol (13 g) and p-toluenesulfonic acid (2.5 g) in 250 ml of dry toluene was refluxed with continous removal of water. After 3 h the reaction mixture was concentrated in vacuo , 2% NaOH (200 ml) was added followed by extraction with dichloromethane. After drying over magnesium sulfate and removal of solvent in vacuo, the remaining red oil was applied to a silica gel column (eluent: ethyl acetate/heptane=1:1) giving 22 g of a slightly yellow oil, 1'-ethoxycarbonyi-spiro[1,3-benzodioxole-2,4'-piperidine].

Provenance & Evidence