Functionalized chloroenamines in aminocyclopropane synthesis part 12. Basicity and protonation behaviour of 6-amino-3-azabicyclo[3.1.0]hexane derivatives

Abstract

Bicyclic endo diamines 1a–c are more basic than the diastereomeric exo diamines 2a–c by about one pK_a unit. Configuration and conformation of some compounds 5, the monoammonium salts of the endo diamines 1, have been studied by ¹H NMR spectroscopy. X-Ray structure analysis of salt 5nBr, possessing the N(3)–H proton in the endo position, indicates a hydrogen bonding with the bromide anion rather than with the C(6)–morpholine unit.