A Prelude to Biogermylene Chemistry**

The biological applications of germylenes remain unrealised owing to their unstable nature. We report the isolation of air-, water-, and culture-medium-stable germylene DPMGeOH ( 3 ; DPM=dipyrromethene ligand) and its potential biological application. Compound 3 exhibits antiproliferative effects comparable to that of cisplatin in human cancer cells. The cytotoxicity of compound 3 on normal epithelial cells is minimal and is similar to that of the currently used anticancer drugs. These findings provide a framework for a plethora of biological studies using germylenes and have important implications for low-valent main-group chemistry.     

Catalytic efficacy of Schiff-base copper(II) complexes: Synthesis,X-ray structure and olefin oxidation

Three copper(II) Schiff-base complexes, [Cu(L¹)(H₂O)](ClO₄) (1), [Cu(L²)] (2) and [Cu(L³)] (3) have been synthesized and characterized [where HL¹ = 1-(N-ortho-hydroxy-acetophenimine)-2-methyl-pyridine], H₂L² = N,N′-(2-hydroxy-propane-1,3-diyl)-bis-salicylideneimine and H₂L³ = N,N′-(2,2-dimethyl-propane-1,3-diyl)-bis-salicylideneimine]. The structure of complex 1 has been determined by single crystal X-ray diffraction analysis. In complex 1, the copper(II) ion is coordinated to one oxygen atom and two nitrogen atoms of the tridentate Schiff-base ligand, HL¹. The fourth coordination site of the central metal ion is occupied by the oxygen atom from a water molecule. All the complexes exhibit high catalytic activity in the oxidation reactions of a variety of olefins with tert-butyl-hydroperoxide in acetonitrile. The catalytic efficacy of the copper(II) complexes towards olefin oxidation reactions has been studied in different solvent media.     

A highly stereocontrolled asymmetric total synthesis of epimer of (+)-7-deoxypancratistatin

A highly stereocontrolled asymmetric total synthesis of epimer of (+)-7-deoxypancratistatin has been achieved from readily available starting materials via unified strategy employing Sharpless asymmetric dihydroxylation, ring closing metathesis, Overman rearrangement, hydrogenolysis and Bischler–Napieralski reaction in 15 purification steps with 15% overall yield.     

Single end-on azido bridged 1D chain copper(II) complex: Synthesis,X-ray crystal structure and catalytic activity in homogeneous epoxidation of cyclooctene

A new azido derivative of a NNO donor tridentate Schiff-base copper(II) complex, [CuL(μ_1,1-N₃)]_n (1) (HL = 1-(N-ortho-hydroxyacetophenimine)-2-(N-ethyl)aminoethane), containing a single end-on μ_1,1-azido bridged 1D infinite chain has been synthesized and characterized. X-ray single crystal structure analysis reveals that the complex [CuL(μ_1,1-N₃)]_n (1) is a 1D chain in which neighboring Cu(II) chromophores are related by glide planes and linked by single azido bridges in the EO mode. No measurable magnetic interaction was evidenced in the complex [CuL(μ_1,1-N₃)]_n (1) through variable temperature magnetic susceptibility measurements (10–300 K). The complex was used as an active catalyst for the epoxidation of cyclooctene using tert-butyl-hydroperoxide as an oxidant. The catalytic activity of the complex has been compared in a series of solvents. The results show that in acetonitrile medium, the epoxide was produced in high yield with high selectivity.     

A trinuclear complex containing MnII MnIII MnIV, radicals, quinone and chloride ligands potentially relevant to PS II

Reaction of MnCl2 with a non-innocent ligand H3L results in an unprecedented mixed-valence trinuclear complex [MnII MnIII MnIV (L)(L*)2(L(IQ))Cl] whose structural and magnetic properties are described.     

A Tandem Reduction–Oxidation Protocol for the Conversion of 1‐Keto‐1,2,3,4‐tetrahydrocarbazoles to Carbazoles via Tosylhydrazones through Microwave Assistance: Efficient Synthesis of Glycozoline,Clausenalene, Glycozolicine,and Deoxycarbazomycin B and the Total Synthesis of Murrayafoline A

A novel and efficient methodology for the synthesis of carbazoles from 1‐keto‐1,2,3,4‐tetrahydrocarbazoles via the corresponding tosylsulfonhydrazones by a one‐pot tandem reduction–oxidation protocol using a combination of NaBH₄ and Pd–C on MgSO₄·7H₂O, a solid support, under microwave is developed. The reaction is successfully extended toward the synthesis of several naturally occurring carbazole alkaloids, namely 3‐methylcarbazole, glycozoline, clausenalene, glycozolicine, murrayafoline A, and deoxycarbazomycin B, a carbazole derivative that is known to have a promising antimicrobial activity.     

Solid-Phase Benzoylation of Phenols and Alcohols in Microwave Reactor: An Ecofriendly Protocol

An efficient solid-phase benzoylation of phenols and alcohols was developed under microwave irradiation. A stoichiometric amount of benzoyl chloride was sufficient to carry out the reaction. This benzoylation features short reaction time, good yields, and easy workup procedures. Furthermore, the scope of the reaction was extended to prepare 3,5-dinitrobenzoyl derivatives of alcohols.