Two Triazole-Based Phosphine Ligands Prepared via Temperature-Mediated Li/H Exchange: Cu^I and Au^I Complexes and Structural Studies

Abstract

The kinetically favored triazole-based phosphine 1-(2-(diphenylphosphino)phenyl)-4-phenyl-1H-1,2,3-triazole (2, L1) and its thermodynamically preferred isomer, 5-(diphenylphosphino)-1,4-diphenyl-1H-1,2,3-triazole (3, L2), were obtained by the temperature-controlled lithiation of 2-bromotriazole followed by the reaction with chlorodiphenylphosphine. The structures of phosphines 2 and 3 were determined by X-ray diffraction. Upon reaction with late transition-metal derivatives (Cu(I), Ag(I), and Au(I)), phosphines 2 and 3 form complexes with monodentate (Cu(I), Ag(I), and Au(I); κ(1)-P), chelate (Cu(I); κ(2)-P,N), bridged bidentate (Cu(I); μ(2)-P,N), and tridentate (Cu(I); μ(2),κ(2)-P,N,N) modes of coordination. Reactions with copper(I) halides produced mono-, di-, and tetranuclear complexes, whereas the reaction of 2 with [Cu(NCCH3)4]BF4 yielded the binuclear complex [Cu2(CH3CN)2{o-Ph2P(C6H4){1,2,3-N3C(Ph)C(H)}-μ-(κ-P,κ-N),κ-N}2](BF4)2 (10) with the ligand acting as a six-electron donor involving phosphorus and two triazole nitrogen atoms. The copper complexes of 2 and 3 containing rhomboid Cu2X2 units, [(Cu)2(μ-X)2{o-Ph2P(C6H4){1,2,3-N3C(Ph)C(H)}-κ-P}2] (4, X = Cl; 5, X = Br), on treatment with 1,10-phenanthroline and 2,2'-bipyridine gave mixed-ligand complexes of the type [(CuX)(N∩N-κ(2)-N,N){o-Ph2P(C6H4){1,2,3-N3C(Ph)C(H)}-κ-P}] (N∩N = 1,10-phen and 2,2'-bipy; X = Cl, Br, and I).

1,2,3-Triazole based bisphosphine, 5-(diphenylphosphanyl)-1-(2-(diphenylphosphanyl)-phenyl)-4-phenyl-1H-1,2,3-triazole: an ambidentate ligand with switchable coordination modes

“…Synthesis of 5-(diphenylphosphanyl)-1-(2-(diphenylphosphanyl)phenyl)-4-phenyl-1H-1,2,3-triazole (2) The temperature-controlled lithiation of 1-(2-bromophenyl)-4phenyl-1H-1,2,3-triazole (1), followed by the treatment of Ph 2 PCl resulted in two different 1,2,3-triazole functionalized monophosphines [o-Ph 2 PC 6 H 4 {1,2,3-N 3 C(Ph)C(H)}] and [C 6 H 5 {1,2,3-N 3 C(Ph)C(PPh 2 )}] depending on the reaction conditions. 13 This method was employed to synthesize triazole based new bisphosphine in one or two step reactions. Treatment of 1-(2-bromophenyl)-4-phenyl-1H-1,2,3-triazole (1) with two equivalents of n BuLi, followed by the addition of two equivalents of Ph 2 PCl yielded bisphosphine [o-Ph 2 P(C 6 H 4 ) {1,2,3-N 3 C(Ph)C(PPh 2 )}] (2) (Scheme 1).…”

“…This paper modes. 13 Although, bidentate mode is common with the triazole based phosphines, the reports on the participation of two nitrogen atoms in coordination is rare. Bisphosphine 2 can act as a potential tetradentate ligand.…”

“…Isolated yield. 36 [AuCl(SMe 2 )], 37 5-(diphenylphosphino)-1,4-diphenyl-1H-1,2,3triazole, 13 1-(2-(diphenylphosphanyl)phenyl)-4-phenyl-1H-1,2,3triazole (A) 13 and 2-iodo-4,6-dimethylphenol 38 were prepared according to the published procedures. Other reagents were obtained from commercial sources and used aer purication.…”

“…2,12 Recently we reported the synthesis of two triazole based mono phosphines by exploiting the temperature controlled Li/H exchange phenomenon and studied their group 11 metals chemistry. 13 As a continuation of our work, herein, we describe the synthesis of C 1 -symmetric triazole based bisphosphine 2. We also demonstrate the ambidentate behavior of ligand 2 with Mo 0 and W 0 metal centers using extensive NMR studies and DFT calculations.…”

The 2‐(4‐Phenyl‐1H‐1,2,3‐triazol‐1‐yl)ethanol‐Based Phosphinite Ligand Ph2POCH2CH2[1,2,3‐N3C(Ph)C(H)] – Synthesis, Transition‐Metal Complexes, and Structural Studies

“…phorus moieties, namely, 1-[2-(diphenylphosphanyl)phenyl]-4phenyl-1H-1,2,3-triazole and 5-(diphenylphosphanyl)-1,4-diphenyl-1H-1,2,3-triazole, through the temperature-mediated Li/H exchange reaction of 2-bromophenyltriazole and explored their coordination chemistry. [6] In this paper, we describe the synthesis of the new 1,2,3-triazole-based phosphinite Ph 2 POCH 2 CH 2 [1,2,3-N 3 C(Ph)C(H)] and its Ru II , Pd II , Pt II , and Au I complexes.…”