Corroles have been vastly utilised in the field of biology, medicine, environment, photophysics etc. Sensing of the hazardous metal ions being one of the most important applications of corroles has rendered fruitful results in biological and environmental sciences. Corroles exhibits exclusive photophysical properties, showing applications in the field of ion chemo sensing by utilizing the absorption and emission phenomena. Corroles have sensing ability towards ions due to the presence of pyrrolic nitrogen atoms, its cavity size, different substituents present on peripheral of corrole and metal atoms present with higher oxidation state in metallocorroles. In this review article, we have described the sensing mechanisms, sensing capabilities and detection limits of corroles for various ions.

A series of four A2B corroles (where A = para-nitrophenyl, and B = 2,3,4,5,6-pentafluorophenyl, 2,6-difluoro, 2,6-dichloro and 2,6- dibromophenyl group) have been synthesized and characterized. These four corroles were tested for the sensing ability towards Hg2+ ion. The LOD for these corroles are comparable to reported sensors for Hg2+ ions. All these our A2B corroles exhibit different fluorescence quenching due to the electronic effect of the phenyl group at C10 position, which has a different halogen atom at 2,6 position of the phenyl ring. A2B free base corroles were synthesized, characterized, and demonstrated as Hg2+ ion sensors. These corroles are highly selective towards the Hg2+ ions and depend on the halogen group substituted on the meso phenyl group.

The 5 A(2)B Mn(III) corroles have been synthesized, fully characterized and used for oxygen atom transfer (OAT) from isolated (oxo)manganese(V)corrole to sulfide. Oxidation of Mn(III) were carried out using ozone, a clean oxidant, which resulted in the isolation of the 5 red- coloured (oxo)manganese(V) corroles. The stoichiometric OAT to a different p-thioanisoles gave a mechanistic insight. The electron withdrawing and electron donating group containing phenyl group substituents on C-10, meso carbon were synthesized to gain effect of substituents on the rate constant. The rate constant suggests the disproportionation reaction for OAT from (oxo)manganese(V) corrole to (oxo)manganese(IV) and (oxo)manganese(VI) corroles. Newly synthesized free bases were characterised by H-1 NMR, UV-visible spectroscopy. Manganese(III) corrole, (oxo)manganese(V) corrole were characterized by UV-visible spectroscopy. Self-decay and oxygen atom transfer to sulfide rate constant were determined using UV-visible spectroscopy. Electrochemistry of these Mn(III) corroles shows the effect of meso phenyl substituents on the oxidation potential of Mn(III) corroles. DFT calculation of these synthesized Mn(III) corroles have been carried out and HOMO-LUMO gap varies with the substituents on meso carbons.

A novel one-pot synthetic method to produce crystalline tri-octylphosphine (TOP) capped iron phosphide nanoparticles is reported here. Standard method of synthesizing FeP includes preparation of a precursor, sodium phosphide, which is finally reacted with ferric chloride (FeCl3).The methods for synthesizing iron phosphide (FeP), reported so far, rely on the use of toxic red or yellow phosphorus to generate the precursor, Sodium phosphide (Na3P). In present investigation, instead of red or yellow phosphorus, a relatively less toxic substance TOP and sodium metal (Na) have been used to yield Na3P. The synthesized nanoparticles were fully characterized by X-ray diffraction pattern (XRD), Infrared spectroscopy (IR), X-ray photoelectron spectroscopy (XPS), Transmission electron microscopy (TEM) and superconducting quantum interference device (SQUID) analyses. The results showed that the synthesized FeP nanoparticles have the characteristic orthorhombic crystal structures, with the size similar to 10 nm and the coercivity 70 Oe at RT.

Four free base corroles, 1-4, A(2)B, (where A = nitrophenyl, and B = pentafluorophenyl, 2, 6-difluoro, 3, 4, 5-trifluoro and 4-carboxymethylphenyl group) have been synthesized, characterized and demonstrated as excellent chemosensor for the detection of fluoride ions selectively in toluene solution. The reported corroles shows highest quantum yield in free base form of porphyrinoid systems so far. All these corrole, 1-4, have the excellent ability to sense fluoride ion. Cumulative effect of static and dynamic factors is responsible for the quenching of fluorescence which indicates the detection of fluoride ion in solution. (C) 2018 Elsevier B.V. All rights reserved.

In this work we have established excellent adsorption properties of Multi-metal citrate complexes for the capture of Organic dyes. These complexes exhibit mesoporous character with pore diameter approximate to 40 angstrom and narrow pore size distribution in their structure as demonstrated by fitting experimental adsorption data into Barrett, Joyner and Halenda (BJH) and Density Functional Theory (DFT) models. Thus these materials have the potential of being used as scavengers for dye stuff removal from industrial waste discharge in the water stream and may replace the high cost carbon adsorbents to capture dye molecules and curb water pollution with resultant toxic, carcinogenic and mutagenic effects of dye stuff on living beings. The mesoporous Zinc, Nickel, Iron, Copper multi-metal citrate complexes with different combinations of these metal ions and citric acid linker have been synthesized under mild hydrothermal conditions through green synthetic pathways. Because of their biocompatibility and non toxicity, these low cost mesoporous materials may prove boon for transport of dyes used as contrast agents during diagnostics applications due to their increased image contrast and chemical stability.

A new general and green synthetic protocol for the synthesis of manganese(III) metallocorroles has been developed from substituted aryl aldehydes and 5-(4-nitrophenyl)dipyrromethane using manganese salt as template. This is the first report in the synthesis of corroles: the formation of direct CC bond through metal initiation. This method allows higher working concentrations than those previously reported. The new A2B manganese(III) metallocorroles were synthesized in good yield for different applications. The single crystal X-ray structure of 10-(3,4,5-fluorophenyl)-5,15-bis(4-nitrophenyl)manganese(III) corrole is also reported and shows that manganese atom is situating atop on macrocyclic plane.