Inherent chirality in calix[8]arenes exploiting the steric constraint of two intercrossing polyether chains

The first example of covalently linked, inhcxently chiral calix[8]arene, 1,4-2,5-calix[8]bis- ca'own-4 3, has been obtained fi'om ¢ithcx 1,4-calix[8]crown-4 1 or p-tert-butylcalix[8]arene by alkylation with Iriethylene glycol ditosylate. The inhexent chirality of 3, due to the steric constraint of the two intercressing crown bridges, is evidenced by signal spliging in the 1H NMR spectrum after addition of Pirkle's reagent