@article {46925,
	title = {Geometrical isomerism directed electrochemical sensing},
	journal = {Analytical Chemistry},
	volume = {92},
	year = {2020},
	month = {MAR},
	pages = {4541-4547},
	type = {Article},
	abstract = {<p>We report the independent role of isomerism of secondary sphere substituents over their nature, a factor often overlooked in molecular electrocatalysis pertaining to electrochemical sensing, by establishing that isomerism redefines the electronic structure at the catalytic reaction center via geometrical factors. UV-vis spectroscopy and X-ray photoelectron spectroscopy suggest that a substituent{\textquoteright}s isomerism in molecular catalysts conjoins molecular planarity and catalytic activation through competing field effects and resonance effects. As a classical example, we demonstrate the influence of isomerism of the -NO2 substituents for the electrocatalytic multi electron oxidation of As(III), a potentially important electrochemical pathway for water remediation and arsenic detection. The isomerism dependent oxidative activation of catalytic center leads to a nonprecious molecular catalyst capable for direct As(III) oxidation with an experimental detection limit close to WHO guidelines. This work opens up an unusual approach in analytical chemistry for developing various sensing platforms for challenging chemical and electrochemical reactions.</p>
},
	issn = {0003-2700},
	doi = {10.1021/acs.analchem.9b05753},
	author = {Kottaichamy, Alagar Raja and Begum, Shabbah and Devendrachari, Mruthyunjayachar Chattanahalli and Bhat, Zahid Manzoor and Thimmappa, Ravikumar and Kotresh, Harish Makri Nimbegondi and Vinod, Chathakudath Prabhakaran and Thotiyl, Musthafa Ottakam}
}
@article {47011,
	title = {Unprecedented isomerism-activity relation in molecular electrocatalysis},
	journal = {Journal of Physical Chemistry Letters},
	volume = {11},
	year = {2020},
	month = {JAN },
	pages = {263-271},
	type = {Article},
	abstract = {<p>The role of electrocatalysts in energy storage/conversion, biomedical and environmental sectors, green chemistry, and much more has generated enormous interest in comprehending their structure-activity relations. While targeting the surface-to-volume ratio, exposing reactive crystal planes and interfacial modifications are time-tested considerations for activating metallic catalysts; it is primarily by substitution in molecular electrocatalysts. This account draws the distinction between a substituent{\textquoteright}s chemical identity and isomerism, when regioisomerism of the -NO2 substituent is conferred at the {\textquoteleft}{\textquoteleft}alpha{\textquoteright}{\textquoteright} and {\textquoteleft}{\textquoteleft}beta{\textquoteright}{\textquoteright} positions on the macrocycle of cobalt phthalocyanines. Spectroscopic analysis and theoretical calculations establish that the beta isomer accumulates catalytically active intermediates via a cumulative influence of inductive and resonance effects. However, the field effect in the alpha isomer restricts this activation due to a vanishing resonance effect. The demonstration of the distinct role of isomerism in substituted molecular electrocatalysts for reactions ranging from energy conversion to biosensing highlights that isomerism of the substituents makes an independent contribution to electrocatalysis over its chemical identity.</p>
},
	issn = {1948-7185},
	doi = {10.1021/acs.jpclett.9b02689},
	author = {Kottaichamy, Alagar Raja and Begum, Shabbah and Nazrulla, Mohammed Azeezulla and Dargily, Neethu Christudas and Devendrachari, Mruthyunjayachari Chattanahalli and Bhat, Zahid Manzoor and Thimmappa, Ravikumar and Kotresh, Harish Makri Nimbegondi and Vinod, Chathakudath Prabhakaran and Thotiyl, Musthafa Ottakam}
}
