Sodium halides as the source of electrophilic halogens in green synthesis of 3-halo- and 3,-dihalobenzo[]thiophenes.

A convenient methodology for the synthesis of mono- and di-halogenated benzo[]thiophenes is described herein, which utilizes copper(II) sulfate pentahydrate and various sodium halides in the presence of substituted 2-alkynylthioanisoles. The proposed method is facile, uses ethanol as a green solvent, and results in uniquely substituted benzo[]thiophene structures with isolated yields up to 96%. The most useful component of this methodology is the selective introduction of bromine atoms at every available position (2-7) around the benzo[]thiophene ring, while keeping position 3 occupied by a specific halogen atom such as Cl, Br or I.

Erratum: μ-Oxalato-bis-[bis-(triphenyl-phosphine)copper(I)] dichloro-methane disolvate. Corrigendum.

An erroneous claim in the paper by Royappa et al. [Acta Cryst. (2013), E69, m126] is corrected and a reference added for a previously published report of a closely related structure.

Tetra-kis(aceto-nitrile)copper(I) hydrogen oxalate-oxalic acid-aceto-nitrile (1/0.5/0.5).

In the title compound, [Cu(CH3CN)4](C2HO4)·0.5C2H2O4·0.5CH3CN, the Cu(I) ion is coordinated by the N atoms of four aceto-nitrile ligands in a slightly distorted tetra-hedral environment.

μ-Oxalato-bis-[bis-(triphenyl-phosphine)copper(I)] dichloro-methane disolvate.

The dinuclear molecule of the title compound, [Cu(2)(C(2)O(4))(C(18)H(15)P)(4)]·2CH(2)Cl(2), lies across an inversion center with a strictly planar bridging oxalate ligand coordinating two Cu(I) ions via two pairs of O atoms. Two triphenyl-phosphine ligands also coordinate each symmetry-related Cu(I) ion, resulting in a distorted tetra-hedral geometry [O-Cu-O = 80.57 (5)° and P-Cu-P = 125.