Synthesis and structure of 2,4,6-tricyclobutyl-1,3,5-trioxane

Abstract

The synthesis and structure of 2,4,6,-tricyclobutyl-1,3,5-trioxane, C15H24O3 1, is described. It was formed in 39% yield during the work-up of the Swern oxidation of cyclobutylmethanol and may serve as a stable precursor of the cyclobutane carbaldehyde. The molecule of 1 occupies a special position (3.m) located at the center of its 1,3,5-trioxane ring. The latter is in a chair conformation, with the symmetry-independent O and C atoms deviating by 0.651 (4) Å from the least-squares plane of the other atoms of the trioxane ring. All three cyclobutane substituents, which have a butterfly conformation with an angle between the two planes of 25.7 (3)°, are in the cis conformation relative to the 1,3,5-trioxane ring. Intermolecular C—H...O interactions between the 1,3,5-trioxane rings consolidate the crystal structure, forming stacks along the c-axis direction. The crystal studied was refined a as a racemic twin.

Keywords

• trioxane
• cyclobutane
• cyclobutane carbaldehyde
• strained rings
• swern oxidation
• crystal structure