Molecular logic operations based on optical detection of sulfur mustard simulant using pyridine appended Mg-porphyrazine complex Dedicated to Late Prof. Dr. Tarkeshwar Gupta.

Selective detection of sulfur mustard simulant, 2-chloroethyl ethyl sulfide (CEES) is performed using specifically designed pyridine appended Mg-porphyrazine complex (1). Interaction of CEES with pyridine units of 1 leads to perturbation/reduction in absorbance of the Q-band of 1 and the process is, thus, monitored using UV-vis spectroscopic method. Interestingly, treating the CEES-1 solution with KMnO₄ solution results in reappearance of Q-band of 1 and allows reuse of 1 by simple filtration. The alkylating ability of CEES and KMnO₄ oxidation of CEES-1 appears to be playing an important role in the detection/degradation process, thereby serving the dual purpose. The chemical sensing is then used as a platform for generating different input-based combinatorial and sequential molecular logic gate(s) allowing facile information processing and as an information security system in the form of a keypad lock.