Synthesis and chiral recognition of optically active crown ethers incorporating a biphenanthryl moiety as the chiral centre
Abstract
Two chiral crown ethers (–)-(S)-(5) and (–)-(R,R)-(6) with a biphenanthryl moiety as the chiral centre have been prepared; examination of their chiral recognition behaviour showed that (–)-(S)-(5) has a very high enantiomer selectivity for 1,2-diphenylethylamine.