4-Ethynyl-2,2,6,6-tetra-methyl-1,2,5,6-tetra-hydro-pyridine N-oxide.

The six-membered ring of the title compound, C11H16NO, has a distorted envelope conformation. The piperidine N atom deviates by 0.128 (1) A from the plane through its three neighbouring atoms. In the crystal structure, mol­ecules are connected by inter­molecular Cethyn­yl—H⋯O contacts to form chains extending in the [10\overline{1}] direction.