Structure of 4-azatricyclo[4.3.1.13,8]undecan-5-one (homoazaadamantanone)

Abstract

C10H15NO, M r = 165.24, monoclinic, P2Jn, a=17.219(1), b=6.4465(5), c=16.064(2)A, fl = 95.95 (1) °, V= 1773.5 (3) A 3, z= 8, Dm= 1.23 (1), D x = 1.24 (1) g cm -3, ,~,(Cu K~t) = 1.5418 A, /z=5.91cm -1, F(000)=720, T=295K. Final R = 0.0474 for 1936 unique observed reflections. In the unit cell, there are two symmetrically independent molecules. The amide group of the first conformational type molecule shows pyramidal arrangement of bonds at N, but this group of the second molecule is almost planar. Each conformational type forms a cyclic dimer by means of inter-amide hydrogen bonds. Introduction. The structure of the title compound (I) was determined as part of a series of studies on the potential occurrence of non-planar amide groups in amides and peptides (Ealick & van der Helm, 1977; Blfiha et al., 1978; Blfiha & Malofi, 1980; Kfilal, Bib.ha & Langer, 1984). This lactam is one of the model compounds in which the cis-amide group is embedded in a rigid tri- cyclic skeleton. Determination of properties characteris- tic for a non-planar amide group, e.g. dependence of chiroptical parameters on the extent and character of deviation from planarity, could be the starting point for finding other similar deviations in flexible amides (peptides) in solution (Blfiha & Malofi, 1980).