A Nanospheric Polyhydrido Copper Cluster of Elongated Triangular Orthobicupola Array: Liberation of H₂ from Solar Energy

Abstract

An unprecedented air-stable, nanospheric polyhydrido copper cluster, [Cu20H11(S2P(O(i)Pr)2)9] (1H), which is the first example of an elongated triangular orthobicupola array of Cu atoms having C3h symmetry, was synthesized and characterized. Its composition was primarily determined by electrospray ionization mass spectrometry, and it was fully characterized by (1)H, (2)H, and (31)P NMR spectroscopy and single-crystal X-ray diffraction (XRD). The structure of complex 1H can be expressed in terms of a trigonal-bipyramidal [Cu2H5](3-) unit anchored within an elongated triangular orthobicupola containing 18 Cu atoms, which is further stabilized by 18 S atoms from nine dithiophosphate ligands and six capping hydrides. The positions of the 11 hydrides revealed by low temperature XRD were supported by a density functional theory investigation on the simplified model [Cu20H11(S2PH2)9] with C3h symmetry. 1H is capable of releasing H2 gas upon irradiation with sunlight, under mild thermal conditions (65 °C), or in the presence of acids at room temperature.

Chinese Puzzle Molecule: A 15 Hydride, 28 Copper Atom Nanoball

“…The average Cu-Cu distance in the square faces of the rhombicuboctahedron about the pseudo C 4 axes (2.65 ) is marginally shorter than for the square faces about the pseudo C 2 axes (2.67 ). [9,14,15] The 1 H NMR spectrum of 1 H exhibits three broad singlet hydride resonances at 4.20, 1.25, and À0.81 ppm with an integration ratio of 6:1:8 ( Figure S8). [12] The diameter of the approximately spherical unit (CH 3 ···CH 3 ) in 1 H is 19.81 , which falls in the range of small nanoparticles; the spherical unit is thus of similar size to the recently reported thiolate-and phosphine-protected (Cu, Ag, and Au) nanoclusters that were fabricated by similar borohydride reductions.…”

“…[7,8] Remarkably, on treatment with excess borohydride, a significant expansion of the nuclearity together with substantial capture of hydride was observed for either of these clusters to yield a molecule that contains 15 hydrides and 28 copper atoms, namely [Cu 28 (H) 15 (S 2 CNR) 12 ]PF 6 (for 1 H : NR = N n Pr 2 ; for 2: NR = aza-15-crown-5). [9] The Cu 28 H 15 cluster cations are airand moisture-stable both in the solid state and in solution. [9] The Cu 28 H 15 cluster cations are airand moisture-stable both in the solid state and in solution.…”

A Fluxional Cu8H6 Cluster Supported by Bis(diphenylphosphino)methane and its Facile Reaction with CO2

“…[2] The phosphine-stabilized hexanuclear copper hydride cluster [CuH(PPh 3 )] 6 ,k nown as 'Stryker's reagent', has been used as aC u ÀHp recursor for regioselective hydrogenation of various carbonyl derivatives. [4a-e,g] and the related compounds, [CuH(PPh 3 )] 5 [4f] and [Cu 8 H 8 (dppp) 4 ] (dppp = 1,3-bis(diphenylphosphino)propane). [4a-e,g] and the related compounds, [CuH(PPh 3 )] 5 [4f] and [Cu 8 H 8 (dppp) 4 ] (dppp = 1,3-bis(diphenylphosphino)propane).…”

“…One dppm ligand (P9,10) bridges the two C 2 related Cu atoms of the Cu 6 core (Cu3, Cu6), and the other four dppm ligands are disposed aroundt he pseudo C 2 axis with connecting the capping Cu atoms to the octahedron. The H107 and H108 atoms bridge on the triangles of (Cu2,4,6) and (Cu1, 3,5), and the H109 and H112 atoms on those of (Cu2,3,7) and (Cu5,6,8), respectively,i nm 3 -fashiona so bserved in [CuH(PR 3 )] 6 (R = NMe 2 , p-tolyl, p-anisyl, R 3 = iPrPh 2 ), [4c,e,g] with the CuÀHd istances ranging from 1.68 to 1.93 .T he disposition of H110 and H111 atoms is largely deformed from the pseudo C 2 symmetry due to asymmetrica rrangements of the phenyl groups on P1 and P5 atoms;t he H110 atom bridges on the inner (Cu1,2,4) triangle but the H111 atom caps the outer (Cu4,5,8) trianglew eakly interacting with Cu1 (2.29 )i nadistorted m 4 -bridging mode (Supporting Information FigureS3c). [4d] Since the crystalso f1 were too small for neutron diffraction study and the hydride positions are not able to be determined precisely by single-crystal X-ray diffraction, the six hydride positions were evaluated by DFT optimization with B3LYP functionals and lanl2dz (for Cu), 6-311 + G(d,p) (for hydride H), and 6-31G(d) (for others) basis sets.…”

Phosphinothiolates as Ligands for Polyhydrido Copper Nanoclusters

“…9 In 2013, Liu et al. published the first Cu 20 nanocluster ligated by dichalcogen donor ligands 9a. Our strategy to obtain Cu nanoclusters involves the use of bidentate ( S , P ) ligands that contain thiolate as a stabilizer and a phosphine that can be used for tuning the electronic properties.…”