Since its first report in 1981, mesitylcopper has become an extremely popular and useful reagent, with many new applications emerging during the past decade. This review summarizes its structural and spectroscopic properties and gives a brief overview of the multitude of fascinating compounds and reactions that have been discovered by using mesitylcopper. Specifically, the role of mesitylcopper in synthesizing oligonuclear homo-and heteroleptic copper(I) frameworks, including biorelevant copper(I) complexes, and the application of mesitylcopper in stoichiometric and catalytic C−C and C−heteroatom bond-forming reactions and as a precursor for nanoparticles and intermetallic phases are covered.

Threefold intramolecular ring-closing metatheses of trans-[MCl2(P{(CH2)(m)CH=CH2}3)2] are effected with Grubbs' catalyst. Following hydrogenation catalyzed by [RhCl(PPh3)3], the title complexes trans-[MCl2(P((CH2)n)3P)] (n=2m+2; M/n=Pt/14, 4 c; Pt/16, 4 d; Pt/18, 4 e; Pd/14, 5 c; Pd/18, 5 e) and sometimes isomers partly derived from intraligand metathesis, trans-[MCl2{P(CH2)n(CH2)n}P(CH2)n)] (4'c-e, 5'e), are isolated. These react with LiBr, NaI, and KCN to give the corresponding MBr2, MI2, and M(CN)2 species (58-99%). (13)C NMR data show that the MX2 moieties rapidly rotate within the diphosphine cage on the NMR timescale, even at -120 °C. The reaction of 4 c and KSCN gives separable Pt(NCS)2 and Pt(NCS)(SCN) adducts (13 c, 28%; 14 c, 20%), and those of 4 c,e and Ph2Zn give PtPh2 species (15 c, 61%; 15 e, 90%). (13)C NMR spectra of 13 c-15 c show two sets of CH2 signals (ca. 2:1 intensity ratios), indicating that MX2 rotation is no longer rapid. Reactions of 4 c or 4'c and excess NaC≡CH afford the free diphosphines P{(CH2)14}3P (91%) and (CH2)14P(CH2)14P(CH2)14 (90%). The latter has been crystallographically characterized as a bis(BH3) adduct. The crystal structures of eight complexes with P(CH2)14P linkages (PtCl2, PtBr2, PtI2, Pt(NCS)2, PtPh2, PdCl2, PdBr2, PdI2) and 15 e have been determined, and intramolecular distances analyzed with respect to MX2 rotation. The conformations of the (CH2)14 moieties and features of the crystal lattices are also discussed.

The defined linear arrangement of metal atoms in discrete coordination complexes or polymers is still one of the most intriguing challenges in synthetic chemistry. These chain arrangements are of fundamental importance, because of their potential applications as molecular wires and single molecule magnets (SMM) in microelectronic devices on a molecular scale. Oligonuclear Group 11 metal complexes with suitable bridging ligands, specifically those that are based on copper as the first choice of a cheap precursor coinage metal, are of particular interest in this regard. This is due to the superior luminescence properties of these linear clusters that often show d10⋅⋅⋅d10 interactions in their molecular structures. The combination of CuI with heavier coinage metal ions results in tunable emissive arrays that are also stimuli‐responsive. Thus, both linear multinuclear CuI and linear heteropolymetallic CuI/AgI as well as CuI/AuI clusters are excellent candidates for applications in molecular/organic light‐emitting devices (OLEDs). Alternatively, paramagnetic multinuclear cupric arrays are prominent as potential molecular wires with enhanced magnetic properties through multiple coupled d9 centers. This Review covers the whole range of linear multinuclear assemblies of cuprous and cupric ions in complexes and coordination polymers, their syntheses, photophysical behavior, and magnetic properties. Moreover, recent advances in the rapidly progressing field of hetero‐CuI/AgI and CuI/AuI molecular strings are also discussed.

Linearly arranged metal atoms that are embedded in discrete molecules have fascinated scientists across various disciplines for decades; this is attributed to their potential use in microelectronic devices on a submicroscopic scale. Luminescent oligonuclear Group 11 metal complexes are of particular interest for applications in molecular light-emitting devices. Herein, we describe the synthesis and characterization of a rare, homoleptic, and neutral linearly arranged tetranuclear Cu(I) complex that is helically bent, thus representing a molecular coil in the solid state. This tetracuprous arrangement dimerizes into a unique octanuclear assembly bearing a linear array of six Cu(I) centers with two additional bridging cuprous ions that constitute a central pseudo-rhombic Cu(I) 4 cluster. The crystal structure determinations of both complexes reveal close d(10) ⋅⋅⋅d(10) contacts between all cuprous ions that are adjacent to each other. The dynamic behavior in solution, DFT calculations, and the luminescence properties of these remarkable complexes are also discussed.