Synthesis, Characterization, and X‐ray Crystal Structures of (Diphosphine)Ni(dmit) and (Diphosphine)Ni(dmio) (Diphosphine = dppv, dppb) Complexes

Abstract

Four complexes with the ligands dmit and dmio were synthesized. Reaction of (PhCO) 2 (dmit) and (PhCO) 2 (dmio) with MeONa afforded the intermediates 2-thioxo-1,3-dithiole-4,5-dithiolate dianion and 2-oxo-1,3-dithiole-4,5-dithiolate dianion, respectively. Reaction of the two dianions with (diphosphine)NiCl 2 [diphosphine = (Z)-1,2bis(diphenylphosphanyl)ethane (dppv), 1,2-bis(diphenylphosphanyl)benzene (dppb)] gave (dppv)Ni(dmit) (1), (dppb)Ni(dmit) (2), * Dr. Y.-L. Li E-Mail: yu_longli@yahoo.cn [a]

Heteroleptic dmit nickel complexes with bis(diphenylphosphanyl)amine ligands as robust molecular electrocatalysts for hydrogen evolution

“…The sum of the angles around the nickel atom is 359.99 (for 1), 360.06 (for 2), 360.35 (for 3), and 360.33 (for 4Á2CH 2 Cl 2 ), respectively. The Ni-S and Ni-P bond lengths for 1-3 and 4Á2CH 2 Cl 2 are comparable with those determined for [RN (PPh 2 ) 2 Ni(bdt)] (R = (CH 2 ) 3 OCH 3 , (CH 2 ) 3 SCH 3 , and CHPhCH 3 [Ni-S: 2.1430-2.1567 Å; Ni-P: 2.1348-2.1701 Å]), [40] [7] Å), [46] (dppv)Ni (dmio) (Ni-S: 2.1681 [7] and 2.1642 [7] Å; Ni-P: 2.1570 [7] and 2.1606[9] Å), [46] and [i-BuN (PPh 2 ) 2 Ni(edt (CH 3 ) 2 )] (Ni-S: 2.1663 [9] and 2.1681 [8] Å; Ni-P: 2.1506 [9] and 2.1561[9] Å). [75] The measured P1-Ni1-P2 and S1-Ni1-S2 bond angles for 1-3 and 4Á2CH 2 Cl 2 are close to those of the analogous nickel complexes.…”

“…[75] The measured P1-Ni1-P2 and S1-Ni1-S2 bond angles for 1-3 and 4Á2CH 2 Cl 2 are close to those of the analogous nickel complexes. [32,36,40,46,59,61,75] The dmit ligands for the complexes are all coplanar configuration duo to the fully conjugated π bonds feature, whereas the fourmembered metallocycle Ni1P1N1P1A are almost coplanar with the mean deviations of 0.046 for 1, 0.018 for 2, 0.005 for 3, and 0.068 for 4Á2CH 2 Cl 2 , respectively. This suggests that the N1 atom in RN (PPh 2 ) 2 ligand adopts sp 2 hybridization due to the influence of coordination.…”

“…Previous published procedure showed the reaction between RN (PPh 2 ) 2 NiCl 2 and in situ formed Na 2 dmit from CH 3 ONa and (PhCO) 2 dmit in absolute methanol and under nitrogen atmosphere [46] only produced low yields of dmit nickel complexes. This study adopted a modified procedure by Jeon et al [49] ;…”

“…This sulfurrich heterocyclic ligand has strong affinities binding to metal ions and demonstrates reversible redox properties. [41] In recent years, a considerable amount of interest has been placed on this dmit complexes [41][42][43][44][45][46] and their applications in organic conductors, [41,47,48] chemical sensors, [49,50] magnetic materials, [42,43] and nonlinear optical materials. [44,49,[51][52][53] As an analogous to dmit, the maleonitriledithiolate (mnt 2− ) complexes also attracted some attentions for the prominent biomimetic and redox properties.…”

“…Inspired by the effective catalytic hydrogen evolution performances of the nickel complexes containing diphosphine and dithiolate ligands, [28,29,32,33] and as a continuation of studies on the heteroleptic nickel complexes, [46,58,59] we herein report the synthesis and structural characterization of four novel heteroleptic nickel complexes bearing RN (PPh 2 ) 2 and dmit ligands, [RN (PPh 2 ) 2 Ni(dmit)] (R = (CH 2 ) 4 CH 3 [1], (CH 2 ) 3 OCH 3 [2], (CH 2 ) 2 CH(CH 3 ) 2 [3], and CHPhCH 3 [4]). These complexes were characterized by elemental analysis, Fourier transform infrared (FTIR), ultravioletvisible (UV-vis), 1 H, 13 C{ 1 H}, and 31 P{ 1 H} nuclear magnetic resonance (NMR) spectroscopies.…”