A conformational study of bicyclo[3.1.0]hexane. Crystal and molecular structure of N′-isopropylidenebicyclo[3.1.0]hexane-6-exo-carbohydrazide

Abstract

A single crystal X-ray diffraction study shows that the bicyclo[3.1.0]hexane skeleton of the title compound (1) exists in a boat conformation and that the five-membered ring system is appreciably flattened compared to cyclopentane. Crystals are triclinic, space group P, with a= 9.89(1), b= 9.53(1), c= 5.602(5)Å, α= 104.71(2). β= 83.59(2), γ= 100.20(1)° and Z= 2; the structure was solved by direct methods and refined by full-matrix least-squares techniques to R 0.056 for 1 649 observed reflections. The conformational properties of the bicyclo[3.1.0]hexane ring system are discussed.