Synthesis, characterization, conduction, and dielectric properties of tetra tert-butylsulfanyl substituted phthalocyanines

Abstract

The tert-butylsulfanylphthalonitrile has been prepared with optimized synthetic procedure. Metal free (H 2 Pc) and metallo phthalocyanines (Pcs) (ZnPc, CoPc, CuPc, PbPc) have been synthesized by cyclotetramerization of tert-butylsulfanylphthalonitrile in the presence of DBU and metal salts. Thus, tertbutylsulfanyl groups enhance the solubility, shift the Q band absorption to the red visible region, and inhibit efficient cofacial interaction of the Pcs (2-6) as evaluated by UV-vis spectra. The electrical conduction and dielectric properties of the synthesized Pc thin films sandwiched between indium tin oxide and aluminum electrodes (ITO-Pc-Al) were investigated from 300 to 500 K. At low bias voltage the conduction is ohmic while at high bias voltage the conduction becomes space charge limited with an exponential distribution of traps. The measured ac conductivity data are discussed in terms of classical models based on pair approximation. It was found that the ac conductivity obeys the power law given by σ ac = σ 0 ω s , in which the frequency exponent s decreases with temperature. The real and imaginary parts of the impedance are found to be dependent on both frequency and temperature.

Some mechanistic insights into the action of facilitating agents on gas permeation through glassy polymeric membranes

“…A tert‐ butyl derivative of cobalt phthalocyanine was prepared to solubilize the phthalocyanine in the solvents used for membrane synthesis. The procedure of making tert‐ butyl cobalt phthalocyanine was as described in the work of Kaipova et al A mixture of 4‐ tert ‐butylphthalonitrile (0.46 mM, 0.10 g), Co(OAc) 2 (0.154 mM, 0.027 g) and a catalytic amount of diazabicycloundecene (DBU) in n‐pentanol (1 mL) were heated to 140°C with stirring for 24 h under N 2 atmosphere. Then, the reaction mixture was cooled to room temperature and allowed to precipitate by adding methanol.…”

Alkylthio-tetrasubstituted μ-Nitrido Diiron Phthalocyanines: Spectroelectrochemistry, Electrical Properties, and Heterojunctions for Ammonia Sensing

“…Materials and methods 4-Nitrophthalonitrile, 43 4-n-butylthiophthalonitrile 1a, 44 4-tert-butylthio-phthalonitrile 1b, 7,45,46 4-hexadecylthiophthalonitrile 1d 47 and the lutetium bisphthalocyanine 48 were synthesized according to published procedures. Xylene was distilled from di-phosphorus pentoxide.…”