Covalently assembled resorcin[4]arenes and molecular tweezers: a chiral recognition rationale by NMR

<p>Chiral diamides and tetramidic resorcin[4]arenes deriving from (<i>R</i>,<i>R</i>)-1,2-diaminocyclohexane and (<i>S</i>,<i>S</i>)-1,2-diphenylethylendiamine, and a valine containing resorcin[4]arene have been compared by NMR in the enantiodiscrimination of mandelic acid. The relevance of cooperation between side arms and external surface of resorcin[4]arene core has been ascertained.</p>