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Abstract

p-Tetrakis(4-nitrophenylazo)tetrahydroxytetrathiacalix [4]arene and p-tetrakis(phenylazo)tetrahydroxytetrathiacalix[4]arene were prepared and fully characterized using 1 H and 13 C NMR, mass spectroscopy, thermogravimetric analysis and differential scanning calorimetry. The solid-state structure of p-tetrakis(4-nitrophenylazo)tetrahydroxytetrathiacalix[4]arene was investigated by single crystal X-ray diffraction. It crystallized in the triclinic system (space group: P1 ¯). z-Scan experiments were performed on the p-tetrakis(4-nitrophenylazo)tetrahydroxytetrathiacalix [4]arene showing non linear absorption due to two photon absorption with a TPA cross-section of about 50610 250 cm 4 s per photon. Optical power limiting measurements on the p-tetrakis(phenylazo)tetrahydroxytetrathiacalix[4]arene at 532 nm (48% linear transmission) was found to limit the energy to y9 mJ.

Optical limiting and nonlinear optical studies of ferrocenyl substituted calixarenes

“…However, the linear transmission values exhibited by FSCs a, b, and c were 57%, 68% and 35% respectively, at 532 nm for 1 mM concentration solution, giving rise to ground state absorption cross-section values of 1.9 × 10 −18 cm 2 , 1.3 × 10 −18 cm 2 and 3.5 × 10 −18 cm 2 , respectively At 150 J input energy, the transmission values for FSCs a, b, and c are 4, 3.5 and 7 times less compared to their respective linear transmission values. Optical limiting performance of FSCs is comparable, rather better (FSC c) than the measurements reported on a modified calix [4]arene, which, was shown to limit energy of a nanosecond laser pulses at 532 nm to 9 J energy [14]. Overall, optical limiting performance of FSCs is comparable to fullerene C 60 and ferrocenyl substituted porphyrins reported recently with the same setup [17], particularly FSC c is the better performer.…”

“…Singh). 532 nm have been reported in tetrathiacalixarene [14] and calixarene bridged metal phthalocyanines [15]. Ferrocene, one of the most widely studied organometallic compound shows strong nonlinear optical behavior [16].…”

Chemistry of Thiacalixarenes

“…The 1 H NMR spectrum of 55 indicates that it prefers the expected cone conformation. A similar reaction pathway was employed recently [53,54] for the synthesis of the azo derivatives of thiacalixarenes, which have potential for use in nonlinear optics.…”

“…[63] Very recently, nitration of the parent thiacalixarene 13 without concomitant oxidation of sulfur atoms was described. [54] The method uses KNO 3 /AlCl 3 in di-, tri-or tetraglyme and gives 5,11,17,23-tetranitro-25,26,27,28-tetrahydroxythiacalix [4]arene (60) in good yields (67 %). The choice of solvent is crucial for the reaction -use of THF, acetonitrile, or toluene did not result in the desired nitration products.…”

“…The preference for the 1,2-alternate conformation in thiacalixarenes seems to be more general. Recently, several other derivatives (namely, unsubstituted thiacalix [4]arenes bearing nitro-or arylazo-groups on the upper rim) were also found [53,54] to adopt this unexpected conformation in solid state. It indicates that the larger cavity of thiacalixarenes leads to a better energy minimization in the 1,2-alternate conformation rather than the cone conformation.…”