Tellurated Schiff Bases Formed from {2‐[(4‐Methoxyphenyl)telluro]ethyl}amine and Bis(2‐aminoethyl) Telluride with o‐Hydroxyacetophenone: Synthesis and Complexation Reactions with Hg^II, Pd^II and Ru^II − Crystal Structures of the Ligands, [Ru(p‐cymene)Cl{H₂NCH₂CH₂TeC₆H₄‐4‐OCH₃}]Cl·H₂O and [RuCl{4‐MeOC₆H₄TeCH₂CH₂NHCH(CH₃)C₆

Abstract

{2‐[(4‐Methoxyphenyl)telluro]ethyl}amine and bis(2‐aminoethyl) telluride on treatment with o‐hydroxyacetophenone gave the Schiff bases 4‐MeOC6H4TeCH2CH2N=C(CH3)C6H4‐2‐OH (L1) and 2‐HOC6H4(CH3)C=NCH2CH2TeCH2CH2N=C(CH3)C6H4‐2‐OH (L3), respectively. The reduction of L1 and L3 with NaBH4 resulted in 4‐MeOC6H4TeCH2CH2NHCH(CH3)C6H4‐2‐OH (L2) and 2‐HOC6H4(CH3)CHNHCH2CH2TeCH2CH2NHCH(CH3)C6H4‐2‐OH (L4), respectively, which have 1 or 2 chiral centers. The 1H and 13C NMR spectra of L1 to L4 were found to be characteristic. Treatment of L1 with [Ru(p‐cymene)Cl2]2 resulted in [Ru(p‐cymene)(4‐MeOC6H4TeCH2CH2NH2)Cl]Cl·H2O (1) whereas in the reaction of L2 with [Ru(p‐cymene)Cl2]2, the p‐cymene ligand is lost resulting in [RuCl(L2‐H)] (4). The reactions of L1, L3 and L4 with HgBr2 resulted in complexes of the type [HgBr2·(L)2] while Na2PdCl4 reacted with L1 to give [PdCl(L1‐H)]. The solid‐state structures of L1, L3, 1 and 4 were determined by single‐crystal X‐ray diffraction studies. The very swift formation of the tellurated amine from a tellurated Schiff base (L1) by hydrolysis has been observed for the first time and has resulted in 1. The Ru−N and Ru−Te bond lengths in 1 are 2.142(3) and 2.6371 (4) Å, respectively. The replacement of the p‐cymene ligand with a hybrid organotellurium ligand (L2‐H), resulting in 4, is also a first example of its kind. The Ru center in 4 has a square‐planar geometry, with the Ru−N, Ru−Te, Ru−O and Ru−Cl bond lengths being 2.041(6), 2.4983(8), 2.058(5) and 2.308(2) Å, respectively. In the crystals of 4 there are secondary intermolecular Te···Cl interactions and intermolecular N−H···O hydrogen bonds. This is the first example in which coordinated Te in a complex is engaged in two intermolecular secondary interactions. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

Synthesis and characterization of some new organotellurium compounds based on quinoline

“…The IR spectra of all new prepared compounds 1-10 show strong absorption band around the region 1614-1691 cm -1 range is characteristic, originating from the stretching mode of the C=N bonds. These values are in good agreement with previous works [2,[9][10][11]. The IR spectra of compounds 2-7 are quite similar to those of 8-(quinolyl)mercuric chloride (1).…”

Synthesis, Characterization andin vitroAntioxidant Activity of New ChiralN-boc Organotellurium Compounds, (CH3)3OC(O)NHCH(R)C(O)NHCH2-CH2Te-C6H4-4-OCH3, Containing Carbamate and Peptide Groups

“…The aromatic protons present at meta and ortho to Te were observed at 6.804-6.9 and 7.606-7.663 ppm respectively in all the compounds which were in agreement with that reported for 2-(4-methoxyphenyltelluro) ethylamine. 55 The peaks for other aromatic protons were characteristic. 56 The other aromatic signals are characteristic for their respective carbons.…”

“…These signals were found deshielded about 0.4 to 0.5 ppm when compared to 2-(4-methoxyphenyltelluro) ethylamine. 55 There are two types of NH groups such as the carbamate (Boc-NH-) and amide (>CO-NH-). The carbamate NH proton gave a doublet in the range of d, 6.5 to 6.9 ppm while the amide NH gave a triplet between 7.95 to 8.25 ppm due to coupling with CH and CH2 protons respectively.…”

“…[52][53][54][55] This latter will then undergo further reactions which control the overall stoichiometry, that is, the number of molecules of DPPH reduced (decolorized) by one molecule of the reductant. The reaction is therefore intended to provide the link with the reactions taking place in an oxidizing system, such as the autoxidation of a lipid or other unsaturated substance; the DPPH molecule is thus intended to represent the free radicals formed in the system whose activity to be suppressed by the substance.…”

Synthesis, characterization, and computational study of some new organotellurium compounds containing azomethine groups

“…Molecular structures of some of these tellurated azomethines in the solid state indicated the existence of the intramolecular Te ← N bond [5,6,[12][13][14][15]. Recently, Singh and coworkers [16] [16]. Furthermore, the condensation of bis(o-formylphenyl) diselenide with (R)-(+)-1-phenylethylamine afforded the chiral azomethine diselenide, (1-phenylethylimino)methyl) phenyl)diselanyl)benzylidene-1-phenylethanamine [17].…”