The structures of ethyl 1,2,2-tricyano-3,3-dimethylcyclopropane-1-carboxylate and ethyl 2',3,3'-tricyanocyclohexanespirocyclopropane-2'-carboxylate

Abstract

The crystal and molecular structures of C₁₁H_1IN₃0₂ (I) and C₁₄H₁₅N₃0₂ (II) have been determined by direct methods using three-dimensional X-ray diffractometer data. Crystals of (I) are orthorhombic, space group Pna2₁, with a=14.662 (6), b=10.492 (5), c=7.375 (3) Å , Z=4, V=1134.5 ų, D_O=1.25 (by flotation), D_e=1.269 Mg m^-3, μ(MoKα)=0.085 mm^-1. Crystals of (II) are monoclinic, space group P2₁/a, with a=7.886 (5), b=22.011 (8), c=8.100 (3) Å, β=103.12 (5)°, Z=4, V =1369.2 ų, D_O=1.23 (by flotation), D_e=1.255 Mg m^-3, μ (MoKα=0.080 mm^-1. Least-squares full-matrix refinement based on 782 (I) and 1400 independent reflections (II) converged at R=0.040 (I) and 0.042 (II). The effect of electron-withdrawing substituents on the geometry of the cyclopropane ring is discussed.