Tetrahedron
The use of immobilized crown ethers as in-situ N-protecting groups in organic synthesis and their application under continuous flow
GP Wild, C Wiles, P Watts, SJ Haswell
Index: Wild, Gareth. P.; Wiles, Charlotte; Watts, Paul; Haswell, Stephen J. Tetrahedron, 2009 , vol. 65, # 8 p. 1618 - 1629
Full Text: HTML
Citation Number: 9
Abstract
In addition to their high affinity for inorganic cations, crown ethers have been shown to efficiently sequester ammonium ions, forming a stable adduct via hydrogen bonding. Using this principle, several authors have reported the use of crown ethers as protecting groups for amines however to date, their widespread use has been somewhat precluded by the difficulties associated with removal of the crown ether from the resulting reaction mixture. ...