Studies on Properties of Tetra‐ p ‐nitro‐tetra‐ O ‐alkylcalix[4]arenes

Ibis paper reports the properties of the novel tetra‐ p ‐nitro‐tetra‐O‐alkyl‐calix[4]arenes (alkyl= n ‐C 4 H 9 , 1; n ‐C 8 H 17 2; n ‐C 12 H 25 , 3; n ‐C 16 H 33 , 4). X‐ray crystallographic analysis and 1 H NMR revealed that they exist as pinched‐cone conformation in crystal or cone conformation in solution. EFISH experiments at 1064 nm in CHCl 3 , indicated that tetra‐ p ‐nitro‐tetra‐ O ‐butyl‐calix[4]arene (1) has higher hyperpolarizability β, values than the corresponding reference compound p ‐nitro‐phenyl butyl ether, without red shift of the charge transfer band. Compounds 2, 3 and 4 with longer alkyl chains can form monolayer at the air/water.