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 pKa 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.