SummaryWe describe the calixarene-cyclodextrin-coupling via click reaction starting from 5,11,17,23-tetra-tert-butyl-25,27-dipropargylether-26,28-hydroxy-calix[4]arene (calix[4]arene-dipropargylether) (2) onto 6I-azido-6I-deoxycyclomaltoheptaose (3) under microwave assisted conditions. The coupling was proven by MALDI-TOF mass spectrometry, 1H NMR and IR-spectroscopy. The pH dependent supramolecular complex formation with poly(NIPAAM) bearing attached adamantyl units was investigated by dynamic light scattering (DLS) and turbidity measurements.

The synthesis of a functionalized calix[4]arene bearing 1,3-dipolaric nitrone groups (5) has been carried out. The reaction of N-methylhydroxylamine or N-propylhydroxylamine with the carbonyl group of 5,11,7,23-tetraformyl-25,26,27,28tetraalkoxycalix[4]arene leads to calix[4]arenes bearing a nitrone function at each of the four para-positions. Via 1,3-dipolar cyclo-addition of acrylic acid methyl ester with the nitrone functions of 5, subsequently an upper rim-substituted tetraisoxalidinecalix[4]arene is quantitatively synthesized. Further, the minimization of shrinkage of a dental filling depending on the amount of calix[4]arene-tetranitrone is discussed.

Calix[4]arenes were double alkylated with various alkylhalogenides and the residual OH functions were subsequently dimethacrylated with methacryloyl chloride. The successful synthesis of polymerizable calixarenes was proved using 1 H NMR spectroscopy, matrix-assisted laser desorption ionization time-of-flight mass spectrometry and differential scanning calorimetry. The polymerization behaviour was confirmed by copolymerization with methacrylic acid methyl ester. Furthermore, the flexural strength, the flexural modulus of elasticity, the exothermic course of the photo-curing reaction and the polymerization shrinkage of experimental dental filling composites containing the modified calixarenes were evaluated. Calix[4]arenedimethacrylate 3 and tetramethacrylate 4 were synthesized via esterfication of 1 with 2 according to Scheme 1. RESULTS AND DISCUSSION

We describe the synthesis of 5,11,17,23‐tetra‐tert‐butyl‐25,27‐dioxypropylphosphonic acid‐26,28‐dimethacryloyloxy‐calix [4]arene and 5,11,17,23‐tetra‐tert‐butyl‐25‐oxypropylphosphonic acid‐27‐hydroxy‐26,28‐dimethacryloyloxy‐calix[4]arene starting from para‐tert‐butyl‐calix[4]arene. The complete reaction was proved by matrix‐assisted laser desorption ionization time of flight mass spectrometry and nuclear magnetic resonance spectroscopy. The influence of these compounds on the kinetics of the radical polymerization of methyl methacrylate was shown by dilatometry. Furthermore, the adhesive properties of dental adhesives containing these calix[4]arene derivatives were investigated. Copyright © 2012 Society of Chemical Industry

The synthesis of 5,11,17,23‐amino‐25,26,27,28‐propoxycalix[4]arene (calix[4]amine, 4) starting from 5,11,17,23‐nitro‐25,26,27,28‐propoxy‐calix[4]arene (3) via microwave‐assisted transfer hydrogenation is reported. Furthermore, the calix[4]amine (4) is functionalized with an acrylamide moiety. The swelling behavior in water, the influence on the glass transition temperature, and the shear modulus of a crosslinked N,N‐dimethylacrylamide (NDA) polymer with 5,11,17,23‐acrylamido‐25,26,27,28‐propoxycalix[4]arene (5) and EGDMA, respectively, are investigated.