Crystal and molecular structure of the conjugated dienalp-Cl-C₆H₄-N(Ac)=CH-C(OAc)-CH=CH-CHO

Abstract

Crystals of N,O-diacetyl-5-p-chloranilino-4-hydroxypenta-2,4-dienal, the degradation product from a Stenhouse salt, belong to the monoclinic space groupP2₁/c witha = 10.845,b = 17.607,c = 8.056 Å, β = 95.87 ° andZ = 4. The structure was solved by the heavy-atom method from intensity data measured out to 1.14 Å⁻¹ with CuKα radiation. Hydrogen atoms were not located. A finalR of 0.098 for the 549 observed terms was attained. The molecule is in thetrans-trans conformation, and the non-hydrogen atoms in the pentadienal chain and N-acetyl group are almost co-planar. Thep-chloraniline and O-acetyl groups lie on the same side of the pentadienal skeleton, and their respective planes are approximately parallel and at right angles to the plane of the chain. The molecules in the crystal structure are held together by van der Waals' interactions.