Sterically Demanding Ethylenediamines and Polyamines for the Stabilization of Main Group Elements in Low Coordination Numbers
Date
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
This thesis explores the reaction of primary amines with 1,2-dibromoethane and 1,3-dibromopropane as a one step synthesis of N,N"-disubstituted ethylenediamines, RNH- CH2CH2-NH-R, N,N"-disubstituted propanediamines, R-NH-CH2CH2CH2-NH-R and N-substituted azetidines RN[(CH2)3]. Unlike earlier approaches in the literature, this method circumvents the use of the highly toxic #-haloamines. The reaction can also be a convenient approach to N,N",N""-trisubstituted diethylenetriamines which form as byproducts in the synthesis of the ethylenediamines and are readily separated by distillation. The respective propylenetriamines were obtained in analogous fashion from 1,3-dibromopropane. The use of N,Nʼ,N”- trisubstituted triamines for the stabilization of low valent main group compounds was exemplified through the synthesis and structural characterization of a phosphenium salt. N,N'-disubstituted ethylenediamines, R-NH-CH2CH2-NH-R" bearing different substituents R are difficult to obtain and require multi-step protocols. This thesis describes their one step synthesis from aziridines and primary amines. The analogous 1,3-propandiamines were obtained from primary amines and azetidines. N-tert-Butylimidazol was obtained through thermolysis of 1,3-di-tertbutylimidazolium chloride and used as precursor for bis carbenes.