An Efficient One-Pot Synthesis of Functionalized Azamacrocycles from Methyl 2-Siloxy-2-vinylcyclopropanecarboxylates
31 December 2001 (online)
The (N)-benzylamine substituted 2-siloxy-2-vinylcyclopropanecarboxylates 5, 7, 9, 10, 13, 15, and 17 upon desilylation-ring opening induced by cesium fluoride and subsequent intramolecular Michael addition-ring closure, afford azamacrocycles 18-22 and 24-26 in moderate to good yields in a one-pot operation. The aromatic spacer in amine precursor 12 does not allow formation of ring 23 due to ring strain. Except in the case of 5, dimers or higher oligomers are not observed.
siloxycyclopropane - benzylamination - intramolecular Michael addition - one-pot synthesis - azamacrocycle