Copper(i) diselenocarbamate clusters: synthesis, structures and single-source precursors for Cu and Se composite materials

Abstract

Neutral tetrahedral [Cu4(Se2CNnPr2)4] (1), monocationic hydride-centered tetracapped tetrahedral [Cu8(H){Se2CNR2}6]+ (R = nPr, 2H; Et, 3H) and neutral hydride-centered tricapped tetrahedral [Cu7(H){Se2CNR2}6] (R = nPr, 4H; Et, 5H) clusters were formed. They are the first Cu(I) complexes supported by dialkyl diselenocarbamates. The as-synthesized complexes 2H and 3H, formed from a reaction mixture of Cu(I) salts, diselenocarbamates, and [BH4]− in an 8:6:1 ratio, can be further reduced to 4H and 5H, respectively, in the presence of one equiv. of [BH4]−. Replacement of [BH4]− with [BD4]− afforded the deuteride analogues [Cu8(D){Se2CNR2}6]+ (R = nPr, 2D; Et, 3D) and [Cu7(D){Se2CNR2}6] (R = nPr, 4D; Et, 5D), which confirm the presence of hydride in the corresponding (2H, 3H, 4H and 5H) compounds. These complexes were fully characterized by elemental analysis, ESI-MS, and 1H, 2H and 77Se NMR spectroscopy, and their molecular structures were unequivocally established by single crystal X-ray crystallographic analyses (1, 2H–5H). The hydride-encapsulated copper frameworks of (2H, 3H) and (4H, 5H) reveal a tetracapped tetrahedral cage of Cu8 and a tricapped tetrahedral cage of Cu7, respectively, which are enclosed within a Se12 icosahedron constituted by six dialkyl diselenocarbamate ligands. Compounds 2H and 3H display orange emission in both the solid and solution state under UV irradiation at 77 K. In addition, the thermolysis behaviors of 2H were studied to demonstrate the potential of these compounds as single-source precursors for copper selenide nanocomposites, which were analyzed by XRD, EDX, and SEM techniques.

Dinuclear Copper Complexes Triply Bridged by a Tetraphosphane, rac‐Ph2PCH2P(Ph)CH2P(Ph)CH2PPh2

“…The bridging chloride anions (Cu–Cl = 2.3646(9)–2.4365(10) Å, Cu–Cl–Cu =64.32(2)–66.09(2)°) might be derived from the solvent CHCl 3 , because a similar reaction in a MeOH/CH 2 Cl 2 mixed solvent did not afford 13 and resulted in very unstable and unidentified products. While tetrahedral µ 4 ‐hydrides were already reported in the Cu I hydride clusters with {Cu 7 H}, {Cu 8 H}, {Cu 20 H 11 }, {Cu 28 H 15 }, and {Cu 32 H 20 } cores, discrete tetrahedral Cu 4 (µ 4 ‐H) complexes are extremely limited only to [Cu 4 (µ 4 ‐H)(µ‐X) 2 (PPh 2 py) 4 ] + (X = Cl, Br; Ph 2 Ppy = 2‐(diphenylphosphanyl)pyridine), which showed symmetrical and shorter C–H distances (av. 1.711–1.727 Å) unlike 13 .…”

Copper clusters are nanoscale materials comprised of a metal core or frame enclosed by a mantle of stabilizing ligands; their exploration offers progress in diverse fields, such as medicine, electronics, and fundamental chemistry as catalysts, reducing agents, corrosion inhibitors, and petroleum sweeteners. When stabilized with dithiocarbamate (DTC) ligands (L), copper clusters show a propensity for reversible hydrogen uptake and a remarkable versatility in size and shape as demonstrated by the facile subs

“…The reversibility of the hydrogen charging-discharging process, its chemical stability, and its high thermal conductivity render the copper-hydride cluster a promising material for applications in energy and transportation fields. The so-called Chinese puzzle ball is only one of many hydride structures that may be produced with varied copper composition, including Cu 6 [13][14][15][16], Cu 7 [17,18], Cu 8 [19][20][21][22], Cu 13 [23], Cu 14 [24,25], Cu 18 [26,27], Cu 20 [25,28,29], Cu 25 [10,30], Cu 29 [31], Cu 32 [32,33], Cu 53 [34], and Cu 61 [35]. Recent work in this fertile field, including the use of copper hydride compounds as catalyst, has been summarized by several authors [36][37][38][39][40][41].…”

Molecular and supramolecular chemistry of mono- and di-selenium analogues of metal dithiocarbamates

“…The remaining structures to be discussed contain copper(I) and are polynuclear. (24) were also structurally characterised in the study [50].…”

“…Although not mentioned in the original publication [50], there is a dithiocarbamate analogue (not isostructural) [100] to the Cu4 diselenocarbamate cluster 22. Non-isostructural analogues for the Cu8 clusters 23 and 24 are also known [101].…”

“…[44][45][46][47][48][49][50][51][52]. Individual results are discussed in the relevant 21 sections below.…”