European Journal of Organic Chemistry issue:21 pages:4122-4129
Oxacalixarenequinazoline macrocycles were prepared in good yields, as mixtures of syn- and anti-isomers, through nucleophilic aromatic substitution cyclocondensation reactions of 2,4-dichloro-quinazolines and m-dihydroxybenzenes. The macrocyclization conditions were optimized and the isomeric ratio was investigated by means of one-step and fragment-coupling approaches. The oxacalixarene substitution pattern could easily be varied by altering the dichloroquinazolinyl biselectrophilic and dihydroxyaryl bisnucleophilic building blocks. The solid-state (1,3-alternate) conformational behaviour and the oxacalixarene cavity size were explored by X-ray diffraction studies.