Ni(II) complexes of dithiophosphonic acids

Abstract

The reaction of 2,4-bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane-2,4-disulfide (Lawesson reagent) with isobutanol, cyclohexylamine and phenylethylamine produced (4-methoxy-phenyl)-phosphonodithioic acid o-isobutyl ester HS 2 P(p-C 6 H 4 OMe) (OCH 2 CH(CH 3) 2) (I), [S 2 P(C 6 H 11 NH)(p-C 6 H 4 OMe) H 3 N + C 6 H 11 ] (II) and [S 2 P(phCH 2 CH 2 NH) (p-C 6 H 4 OMe)H 3 N + CH 2 CH 2 ph] (III), respectively. The reaction of alcohol with Lawesson reagent produced neutral product (I) while that with amines led to an ion pair (II, III). Furthermore, reaction of I, II and III with NiCl 2 .6H 2 O in methanol produced novel complexes: IV, V and VI. The compounds were characterized by 1 H, 13 C and 31 P NMR, IR spectroscopy and elemental analysis. The single crystal X-ray structures of IV and V showed that the nickel complexes are square planar. Compound V formed a three-dimensional supramolecular structure via intermolecular P-O.. .H-N hydrogen bonds. The Xray crystallography of V showed that those three hydrogens of + NH 3 cation produced three hydrogen bonds with different distances. The new compounds were additionally tested in view of their anti-bacterial properties. The ligands containing amine substituents exhibited more activity toward tested bacteria than their alcohol substituents, while the Ni(II) complexes including alcohol substituents exhibited high potential.

Antibacterial Activity of Amidodithiophosphonato Nickel(II) Complexes: An Experimental and Theoretical Approach

“…It is interesting to note that the bond lengths and angles of the -POS 2 moiety are comparable with those found in similar neutral and anionic dithiophosphonato nickel complexes described as bearing either a P=O or P-OH bond [7][8][9][10][33][34][35][36][37][38][39][40]. It is therefore very difficult (from comparison of the crystallographic P-O and/or P-S bond lengths alone) [7][8][9][10][33][34][35][36][37][38][39][40], to discriminate between purely single and double P-O bonds in this class of compounds, or to confidently assign the negative charge on either the oxygen or on the sulphur atoms. Additionally, the [ArPOS 2 ] − fragments are often engaged in strong H-bonds with counterions, which affects the bond lengths between the atoms involved.…”

“…Compounds (BzNH3)2[Ni(dtp)2]•2H2O (black triangle in Figure 4) and (PhBuNH3)2[Ni(dtp)2] (red triangle in Figure 4) lie in the same region as the anionic fragments. It is worth noting the three blue squares lying in the same region as the yellow dots: these data refer to structures (IKOSUX and LIFGAJ) [10,[33][34][35][36][37][38][39][40] containing single P─OH bonds in neutral fragments, thus confirming the proposed correlation.…”

“…A better understanding of the nature of the P-O bond (and its charge distribution) may be gleaned if the bond lengths involved in the -POS 2 fragment are considered together. The correlation reported in Figure 4 suggests that purely double P=O bonds may only be found on P(O)S 2 fragments not directly bearing a negative charge (empty green circles, CCDC ref-codes IDUNEC, NEYLUA, NEYMAH, and YABQEZ) [7][8][9][10][33][34][35][36][37][38][39][40]. Similarly, pure single P-O bonds are detected in neutral O-alkyl-dithiophosphonates (III in Scheme 1, yellow circles in Figure 4).…”

Synthesis and structural characterization of Pd(II) and Cu(I) complexes containing dithiophosphorus ligand and their catalytic activities for Heck reaction

“…Titled compound was prepared using reported method [61]. To a suspension of Lawesson's reagent (0.404 g, 1 mmol) in 10 mL dry toluene at room temperature, benzylamine (0.536 g, 5 mmol) was added and the mixture was stirred for 6h.…”

Synthesis, characterization, and molecular structures of Ni(II) and Cd(II) complexes derived from dithiophosphonate

“…[17][18][19][20] In the last decades, some of square planar and octahedral Ni(II) complexes [21][22][23] and tetrahedral Cd(II) complexes [24][25][26] have been reported. Our interest in the coordination chemistry of dithiophosphinate ligands [27] boosted us to investigate the synthesis and characterization of a new, dianionic, S-donor ligands (1 and 2) and their coordination properties toward Ni 2+ and Cd 2+ metals. Dithiophosphonates 1 and 2 can be easily synthesized starting from the Lawesson's dimer [S 2 P(p-C 6 H 4 OMe)] 2 (scheme 1) since under suitable conditions, it can give a ring-opening reaction by nucleophilic attack.…”