Journal of Chemical Sciences [Formerly: Proceedings (Chemical Sciences)] Vol. 124, No. 6, November 2012 CONTENTS Special issue on Modern Trends in Inorganic Chemistry (MTIC-XIV)

Foreword ...... 1143

Mechanism of -O–O- bond activation and catalysis by RuIII-pac complexes (pac = polyaminocarboxylate) Debabrata Chatterjee...... 1145–1150

Ru-pac (pac = polyaminocarboxylate) complex catalysed -O–O- bond t activation in H2O2, BuOOH and KHSO5 leading to the formation of various catalytically active species, viz. [RuIII(pac)(OOH)]2j, [RuIV(pac)(OH)]j and [RuV(pac)(O)]j, and their reactivity towards oxidation of cysteine and azo-dye.

Helical chirality induction of expanded porphyrin analogues

Jun-Ichiro Setsune ...... 1151–1163

Based on the fact that binding chiral ligands cause excess of unidirectional helical chirality in the cyclooctapyrrole O1 with 32p-cycloconjugation, helical chirality induction in the CuII complexes of cyclooctapyrrole O2 with interrupted p-conjugation and the dinuclear CoII complexes of cyclotetrapyrroletetrapyridine O3 is demonstrated.

Organometallic complexes of the metals: Synthesis, structure, and catalytic applications M = H, Cl M Piyali Paul and Samaresh Bhattacharya ...... 1165–1173 C H If an alkyl or aryl CjH bond of a judiciously chosen ligand is brought in close C proximity to a platinum metal-bound hydride or chloride by coordination I II through regular donor atoms (as in I), then facile activation of that CjH bond takes place leading to the formation of cyclometallated species (II).

Digestive ripening: a synthetic method par excellence for core– shell, alloy, and composite nanostructured materials Srilakshmi P Bhaskar and Balaji R Jagirdar...... 1175–1180

Solvated Metal Atom Dispersion method in combination with digestive ripening process is presented as a powerful synthetic method for realizing highly monodisperse metal, core–shell, alloy, and composite nanoparticles.

Electronic structures of complexes encircling non- innocent ligand assembly

Amit Das, Dipanwita Das, Tanaya Kundu and Goutam Kumar Lahiri...... 1181–1189

The sensitivity concerning the electronic structural aspects of the ruthenium complexes with non-innocent ligands (L) in accessible redox states could be convincingly addressed via the critical and collective analysis of crystal structures, magnetism, spectroelectrochemistry in combination with DFT calculations.

1137 1138 Contents

Simple tertiary phosphines to hexaphosphane ligands: Syntheses, transition metal chemistry and their catalytic applications

Maravanji S Balakrishna, Sowmya Rao and Bimba Choubey ...... 1191–1204

Studies on synthesis, transition metal chemistry and catalytic applications of several phosphorus-based ligands have been presented.

Reactions of a stable dialkylsilylene and their mechanisms

Mitsuo Kira ...... 1205–1215

Studies of the reactions of isolable dialkylsilylene 1 have revealed that the reaction modes are not limited to A bond insertion and : bond addition but more diversified including the bimolecular photoreactions, one-electron reduction, and intramolecular isomerization.

Cu(II) complexes of glyco-imino-aromatic conjugates in DNA binding, plasmid cleavage and cell cytotoxicity

OH Amit Kumar, Atanu Mitra, Amrendra Kumar Ajay, Manoj Kumar Bhat HO O O O OH and Chebrolu P Rao ...... 1217–1228 Cu Cu N N HO O O Spectral studies primarily suggest that the complexes of C2-glucosyl conjugates O OH HO bind to DNA through intercalation. Copper complexes were found to cleave the plasmid DNA as well showed toxicity to HeLa and MCF–7 cell lines, suggestive of apoptotic cell death. Dinuclear complexes do bind better than the mononuclear ones.

Cu(I)/Cu(II) templated functional pseudorotaxanes and rotaxanes

Subrata Saha and ...... 1229–1237

The synthetic strategies developed to construct pseudorotaxanes and rotaxanes using Cu(I)/Cu(II) ions as template and interesting properties of selected threaded complexes are discussed.

Linear, branched and network polysilanes with thienyl/furyl substituted sila-alkyl side chains and their applications for the

R synthesis of fluorescent silver nanoparticles/clusters Me Si Ravi Shankar, Usharani Sahoo, Vandana Shahi PhMeSiCl + ThMe Si(CH ) SiCl Na, THF 2 2 2 2 3 Si Si – RT x 1-x n and Manchal Chaudhary ...... 1239 1244 Ph R

R= ThMe2Si(CH2)2 Synthetic methods for a few linear, branched and network polysilanes Branched polysilane bearing thienyl/furyl substituted sila–alkyl side chains are described. These polymers are useful precursors for in situ reduction of Ag(I) ions and afford stable polymer–silver nanoassemblies with control over the size domains. Photoluminescence properties of these nanoassemblies are also reported. Contents 1139

Chalcogenated Schiff bases: Complexation with (II) and Suzuki coupling reactions Pradhumn Singh, G K Rao, Mohd Salman Karim and Ajai K Singh ...... 1245–1253

Chalcogenated Schiff bases of 5–chloroisatin (L1–L3), 2–(methythio)- benzaldehyde (L4), 2–acetylpyridine (L5) and benzaldehyde (L6–L7) and palladium complexes of L4–L7 have been synthesized and characterized by 1H, 13C{1H}, 77Se{1H} and 125Te{1H} NMR. The Pd–complexes of L6–L7 even at 0.006 mol% give good conversions in Suzuki−Miyaura coupling (TON upto 1.58 × 104).

Click-generated triazole based ferrocene-carbohydrate bioconjugates: A highly selective multisignalling probe for Cu(II) ions Arunabha Thakur, Sinjinee Sardar

1.5x10-5 Electrochemical Spectrochemical – 4.0 and Sundargopal Ghosh ...... 1255 1260 1.0x10-5 3.5

3.0 5.0x10-6 2+ 2.5 The Cu -specific colorimetric sensors 2,C46H56O20N6Fe and 3, 0.0 2.0 Abs.

Current (A) 1.5 -6 C H O N Fe based on ferrocene-carbohydrate bioconjugates, were -5.0x10 28 33 10 3 1.0

0.5 -1.0x10-5 designed and synthesized in good yields. Both the compounds 2 and 3 0.0 2+ 0.0 0.2 0.4 0.6 0.8 1.0 200300400500600700800 Potential (V) behave as selective chromogenic and electrochemical chemosensor for Cu ion Wavelength(nm) in aqueous environment.

Metal derivatives of heterocyclic-2-thiones: Variable donor ability, C–S rupture and new structural motifs

dmso Tarlok S Lobana and Razia Sultana ...... 1261–1268 CuBr + MeN NH air S The chemical reactivity of heterocyclic-2-thiones, namely, pyridine-2-thione (SNC5H5), imidazolidine-2-thione (SN2C3H6), imidazoline-2-thione (SN2C3H4), 1-methyl-imidazoline-2-thione (SN2C4H6) and thiazolidine-2- thione (S2NC3H5) towards different metal ions is described with special reference to the effect of solvents on synthesis, structures and rupture of C–S bond or C–N bond formation.

Mechanistic studies of copper(II)-mediated oxidation of vic- dioxime to furoxan Oindrila Das and Tapan Kanti Paine ...... 1269–1273

Copper(II) salts in acetonitrile oxidize vic-dioximes to furoxans gave high yields under ambient conditions. A dioximate-copper(II)-dinitrosoalkene intermediate is implicated in the reaction pathway.

Crystallization of organically templated phosphomolybdate cluster-based solids from aqueous solution Minakshi Asnani, Dinesh Kumar, T Duraisamy and Arunachalam Ramanan ...... 1275–1286

Two types of phosphomolybdate clusters, fully oxidised Strandberg-type, VI V {P2Mo5 O23} and fully reduced {P4Mo6 O31} are crystallized with appropriate inorganic and/or organic cations from aqueous solutions containing sodium molybdate and an organic amine (morpholine, HMTA and ethylenediamine). The paper discusses the influence of pH and temperature in dictating the nature of the cluster and the supramolecular interactions. 1140 Contents

Calixarenes: Versatile molecules as molecular sensors for ion

)) recognition study α 2 1.2x107 0 Subrata Patra, Debdeep Maity, Ravi Gunupuru, Pragati Agnihotri 8.0x106 (Log(Fo-F)/(F-F – O OH OH O -6.3 -5.6 -4.9 and Parimal Paul ...... 1287 1299 Log[M]

O O 4.0x106 NH HN Ion-recognition property of a large variety of calix[4]arenes incorporating Hg2+ crown moiety to make hybrid ionophore, substituents to impose steric crowding 0.0 N N 336 392 448 and fluoregenic moieties as signalling unit has been reported. This report demonstrates how factors such as sizes of the ionophore and metal ions, donor atoms, steric crowding and solvents, influence ion-selectivity.

Synthesis, characterization and phosphotriesterase mimetic activity of some Zn(II) and Cu(II) complexes

Mamata Singh, Ray J Butcher, Jerry P Jasinski, James A Golen and ...... 1301–1313

Synthesis and phosphotriesterase (PTE) activity of three Zn(II) and Cu(II) complexes based on bis-phenolate ligands are described. The structures of these complexes were studied by spectroscopic and single crystal X-ray techniques. The mononuclear Zn(II) complex having coordinated water ligands exhibited high PTE activity as compared to the binuclear Zn(II) and Cu(II) complexes.

Fabrication of optochemical and electrochemical sensors using thin films of porphyrin and phthalocyanine derivatives

Palanisamy Kalimuthu, Arumugam Sivanesan – 20 and S Abraham John ...... 1315 1325

10 Thin films of meso-tetramesitylporphyrin on glass slide and 1,8,15,22- tetraaminometallophthalocyanine on GC electrode were fabricated for the 0

–0.2 0 0.2 0.4 0.6 optochemical detection of HCl gas and electrochemical determination of L-cysteine. E/V vs. Ag/AgCl (KCl sat)

Photocytotoxic lanthanide complexes

Akhtar Hussain and Akhil R Chakravarty ...... 1327–1342

The emerging chemistry of lanthanide complexes showing photo-induced DNA cleavage activity and photocytoxicity in cancer cells is reviewed. Lanthanide complexes of pyridyl bases show significant photocytotoxicity in HeLa cells in UV-A light of 365 nm. The cell death is apoptotic in nature as revealed from the fluorescence microscopic studies.

Computational tools for mechanistic discrimination in the reductive and metathesis coupling reactions mediated by titanium (IV) isopropoxide

Akshai Kumar and Ashoka G Samuelson ...... 1343–1352

Computational studies carried out at the B3LYP/LANL2DZ level throw light on the contrasting reactivity of isocyanates and isothiocyanates towards titanium(IV) alkoxides. While both mono and double insertion reactions are feasible with isocyanates, only the mono insertion reaction appears to be thermodynamically feasible with isothiocyanates. Multilayer calculations are also performed on multinuclear titanium intermediates in diastereoselective coupling reactions initiated by low valent titanium species. These studies clearly predict that the coupling of a trinuclear titanium complex involvng alkoxy bridges gives rise to diastereoselective coupling. Non bridged forms and dimeric species would not result in the observed diastereoselectivity. Contents 1141

μ-Phenoxo-μ-pseudohalide and μ-pseudohalide dinuclear, tetranuclear and one-dimensional complexes: magneto-structural correlation and interesting type of solid state isomerism Sujit Sasmal and Sasankasekhar Mohanta ...... 1353–1364

This article reviews some recent studies on metallo-pseudohalide compounds, only pseudohalide bridged or heterobridged 2-phenoxo-21,1-azide/cyanate complexes, and focuses on the following features: (i) unprecedented type of structures; (ii) unique bridge distance dependency of exchange integral; (iii) experimental and density functional theoretical magneto-structural correlations; Heterobridged μμ-phenoxo- 1,1-azide dinickel(II) compounds (iv) interesting magnetic, crystallographic and supramolecular isomerisms.

Study of h6- cyclic p-perimeter hydrocarbon ruthenium complexes bearing functionalized pyridyl diketones: Isolation of complexes with k2-N∩O and k4-N∩O bonding modes of ligands Saphidabha L Nongbri, Babulal Das and Mohan Rao Kollipara ...... 1365–1375

Monomeric and dimeric areneruthenium complexes bearing ligands, 1-phenyl- 3-(2-pyridyl)propane-1,3-dione (pppdH) and 1,3-di(2-pyridyl)propane-1,3- dione (dppdH) with k2-N∩O and k4-N∩O binding modes have been isolated and their structures elucidated.

Rhomboidal [Cu4] coordination cluster from self-assembly of two asymmetric phenoxido-bridged Cu2 units: Role of μ1,1-azido clips Avijit Sarkar, Aloke Kumar Ghosh, Moumita Pait, Haridas Mandal, Tufan Singha Mahapatra, Biswajit Sharangi, Mrinal Sarkar and Debashis Ray ...... 1377–1383

In the presence of sodium azide copper(II) nitrate reacts with 2,6-bis(2- benzoyl-4-chloro-phenylimino)-methyl)-4-methylphenol to give a tetranuclear copper(II) complex resulting from incorporation of two solvent derived methoxide anions.

Single crystal growth of europium and ytterbium based intermetallic compounds using metal flux technique Sumanta Sarkar and Sebastian C Peter ...... 1385–1390

Metal flux is an important synthetic tool in solid-state chemistry for both crystal-growth studies and exploratory studies of europium and ytterbium-based intermetallic compounds. Large single crystals of EuGe2, EuCoGe3 and Yb2AuGe3 compounds were obtained in high yield from the reactions of the elements in liquid indium.

Metal azides under pressure: An emerging class of high energy density materials G Vaitheeswaran and K Ramesh Babu ...... 1391–1398

The calculated total and partial density of states of LiN3 (left) at 60 GPa and KN3 (right) at 16 GPa are shown. Clearly, as pressure increases the width of the p-states of ‘N’ atom in the valence band increases in both the compounds implying that the intra molecular interactions between the N atoms of the azide ion enhance under pressure. 1142 Contents

Mechanism of unusual polymorph transformations in calcium

Mother Liquor Distilled water carbonate: Dissolution-recrystallization vs additive-mediated Reflux – 180 mins Reflux – 75 mins nucleation

Aragonite Vaterite Calcite Arpita Sarkar and Samiran Mahapatra...... 1399–1404

In presence No additive of Lauric Acid Polymorphic transformation from one crystalline form to the other occurs either Na2CO3+ CaCl2 by dissolution-recrystallization mechanism or by additive mediated preferred

Calcite Calcite + Aragonite nucleation. Metastable polymorphs can be stabilized controlling such reaction conditions.

Synthesis, characterization and cytotoxic activity of palladium (II)

Pentose and hexose tBuOH/H2O, 2 h, rt carbohydrate complexes + Sugars N N N3 CuSO4, Sod. ascorbate Pentose and hexose N N Sugars N S Bhavya Deepthi, Rajiv Trivedi, P Sujitha, C Ganesh Kumar, B Sridhar and Suresh K Bhargava ...... 1405–1413 [Pd(COD)Cl2], DCM rt, 2h Pyridyl-carbohydrate triazole ligands were prepared by means of Cu(II) Pentose and hexose N Sugars catalysed 1,3-dipolar cycloaddition reaction. Palladium (II) complexes were N Pd N prepared by treating these ligands with [Pd(COD)Cl ]. The ligands and their Cl N 2 Cl palladium complexes were studied for their cytotoxic activity.

Subject Index ...... 1415–1438 Author Index ...... 1439–1450 Volume Contents...... i–xi

Apoptotic Cells

ROS

Cover picture: Cu(I)/Cu(II) templated synthesis of pseudorotaxanes and rotaxanes with various interesting chemical, switching and mechanical properties (left figure). For details, see the paper by Subrata Saha and Pradyut Ghosh (pp. 1229–1237). Photocytotoxic lanthanide complexes (right figure). For details, see the paper by Akhtar Hussain and Akhil R Chakravarty (pp. 1327–1342).

Indexed in CURRENT CONTENTS ISSN 0974-3626 Edited and published by N Mukunda for the Indian Academy of Sciences, Bangalore 560 080. Printed at Printek Printers, Bangalore 560 079.