1,4-Diaza-spiro[5.5]undecan-3-one

1,4-diazaspiro[5.5]undecane-3-one is a heterocyclic derivative and is mainly used as a pharmaceutical intermediate.

It has been discovered that 1,4-Diaza-spiro[5.5]undecan-3-one and structural analogues can be advantageously prepared in a two-pot process from cyclohexanone. In the first pot, cyclohexenone is reacted with nitromethane to produce 1-(nitromethyl)cyclohexan-1-ol, which then loses water to produce (nitromethylene)cyclohexane. An alkyl glycinate is then added to (nitromethylene)cyclohexane to produce alkyl (1-(nitromethyl)cyclohexyl)glycinate. Then in the second pot, the nitro group of (1-(nitromethyl)cyclohexyl)glycinate is converted to an amino group to produce methyl (1-(aminomethyl)cyclohexyl)glycinate. The alkyl group is then removed to produce (1-(aminomethyl)cyclohexyl)glycine. This compound then internally cyclizes to produce 1,4-Diaza-spiro[5.5]undecan-3-one.