2,5-Bis{[(−)-(S)-1-(4-bromophenyl)ethyl]iminomethyl}thiophene

Abstract

The title compound, C22H20Br2N2S, was synthesized under solvent-free conditions. The mol­ecule shows crystallographic C 2 symmetry, with the S atom of the central thio­phene ring lying on a twofold rotation axis. Furthermore, as a consequence of the (S,S) stereochemistry, the mol­ecule has a twisted conformation. The dihedral angle between the thio­phene and benzene rings is 72.7 (2)° and that between the two benzene rings is 55.9 (2)°. In the crystal, mol­ecules are arranged in a chevron-like pattern, without any significant inter­molecular inter­actions.

Crystal structures of four chiral imine-substituted thiophene derivatives

“…The dihedral angle between the benzene rings is close to that observed for (II): 64.18 (8) for (III) and 62.03 (9) for (IV). The same Schiff base but with Br as the halogen substituent has been published previously (Mendoza et al, 2014), but is not isomorphous with (III) and (IV). Instead, this molecule was found to crystallize in the space group C2, with unit-cell parameters and a crystal structure very similar to those of (II).…”

“…The azomethine bond, which is isoelectronic with the vinyl bond and possesses similar optoelectronic and thermal properties, is easily accessible through the Schiff condensation under near ambient reaction conditions (Morgan et al, 1987;Pé rez Guarìn et al, 2007;Sicard et al, 2013). ISSN 2056-9890 We report here the synthesis and X-ray characterization of such thiophene derivatives, as a continuation of a partially published record (Bernè s et al, 2013;Mendoza et al, 2014). We are improving a general solvent-free approach for these syntheses, recognising that ecological aspects in organic chemistry have become a priority, in order to minimize the quantity of toxic waste and by-products, and to decrease the amount of solvent in the reaction media or during work-up (Tanaka & Toda, 2000;Noyori, 2005).…”

Crystal structure ofN,N′-[(thiophene-2,5-diyl)bis(methanylylidene)]di-p-toluidine

“…For the synthesis of the title compound, see: Vaysse & Pastour (1964). For the syntheses and crystal structures of molecules related to the title compound, see: Bernè s et al 2013; Mendoza et al (2014). For applications of symmetrical diazomethines, see: Suganya et al (2014); Skene & Dufresne (2006).…”

“…For applications of symmetrical diazomethines, see: Suganya et al (2014); Skene & Dufresne (2006). For related structures, see: Bolduc et al (2013 Data collection: CrysAlis CCD (Oxford Diffraction, 2009); cell refinement: CrysAlis RED (Oxford Diffraction, 2009); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS2014 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: SHELXL2014 (Sheldrick, 2015 (Bernès, et al 2013;Mendoza, et al 2014), in cation sensors (Suganya, et al 2014) and in photoactive materials (Skene & Dufresne, 2006).…”

“…The resulting mixture was refluxed for 24 h and the yellow solution was concentrated open to the air, producing a yellow solid. The synthesis of the title compound was also accomplished using solvent-free direct grinding method (Bernès, et al 2013;Mendoza, et al 2014). The solid was purified by recrystallization in an equal volume mix of toluene and methanol.…”