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Treatment of the Cu^Iprecursor [Cu(NCMe)₄]PF₆with excess (10 equivalents) of relatively bulky xylyl isocyanide formed a tetra(isocyanide) complex, namely, tetrakis(2,6-dimethylphenylisocyanide)copper(I) hexafluorophosphate, [Cu(C₉H₉N)₄]PF₆or [Cu(CNXyl)₄]PF₆, in good yield. This is in contrast to the previously reported reactions of Cu^Iprecursors with approximately three equivalents of xylyl isocyanide, which led selectively to the formation of tris(isocyanide) complexes. The copper atom lies on a twofold axis and P atom on an inversion centre. The complex was characterized by X-ray crystallography, IR spectroscopy, and¹H/¹³C {¹H} NMR spectroscopy. In the crystal structure, each individual [Cu(CNXyl)₄]⁺molecule demonstrates two pairs of coplanar xylyl isocyanide ligands. This arrangement leads to intermolecular π-stacking interactions between nearby complex molecules. 

[Mo^VIO₃(L^cat)]²⁻forms a Cu(i)-supported dimeric structure that spontaneously disproportionates into [Mo^VIO₂(L^cat)₂]²⁻and molybdate. This suggests a similar transformation of [{MoO₃(MPT)}₂]⁴⁻into [MoO₂(MPT)₂]²⁻by MobA is feasible. 

The reaction of Fe(OR)₂(THF)₂(OR = bulky alkoxide ligand) with PhIC(CO₂Me)₂results in the formation of reactive remote carbene/vinyl radical intermediate that undergoes facile cyclopropanation or dimerization. 

A new sterically bulky chelating bis(alkoxide) ligand 3,3′-([1,1′:4′,1′′-terphenyl]-2,2′′-diyl)bis(2,2,4,4-tetramethylpentan-3-ol), (H 2 [OO] tBu ), was prepared in a two-step process as the dichloromethane monosolvate, C 36 H 50 O 2 ·CH 2 Cl 2 . The first step is a Suzuki–Miyaura coupling reaction between 2-bromophenylboronic acid and 1,4-diiodobenzene. The resulting 2,2′′-dibromo-1,1′:4′,1′′-terphenyl was reacted with t BuLi and hexamethylacetone to obtain the desired product. The crystal structure of H 2 [OO] tBu revealed an anti conformation of the [CPh 2 (OH)] fragments relative to the central phenyl. Furthermore, the hydroxyl groups point away from each other. Likely because of this anti – anti conformation, the attempts to synthesize first-row transition-metal complexes with H 2 [OO] tBu were not successful. 

Reaction of LiOC t Bu 2 Ph with TlPF 6 forms the dimeric Tl 2 (OC t Bu 2 Ph) 2 complex, a rare example of a homoleptic thallium alkoxide complex demonstrating formally two-coordinate metal centers. Characterization of Tl 2 (OC t Bu 2 Ph) 2 by 1 H and 13 C NMR spectroscopy and X-ray crystallography reveals the presence of two isomers differing by the mutual conformation of the alkoxide ligands, and by the planarity of the central Tl–O–Tl–O plane. Tl 2 (OC t Bu 2 Ph) 2 serves as a convenient precursor to the formation of old and new [M(OC t Bu 2 Ph) n ] complexes (M = Cr, Fe, Cu, Zn), including a rare example of T-shaped Zn(OC t Bu 2 Ph) 2 (THF) complex, which could not be previously synthesized using more conventional LiOR/HOR precursors. The reaction of [Ru(cymene)Cl 2 ] 2 with Tl 2 (OC t Bu 2 Ph) 2 results in the formation of a ruthenium( ii ) alkoxide complex. For ruthenium, the initial coordination of the alkoxide triggers C–H activation at the ortho -H of [OC t Bu 2 Ph] which results in its bidentate coordination. In addition to Tl 2 (OC t Bu 2 Ph) 2 , related Tl 2 (OC t Bu 2 (3,5-Me 2 C 6 H 3 )) 2 was also synthesized, characterized, and shown to exhibit similar reactivity with iron and ruthenium precursors. Synthetic, structural, and spectroscopic characterizations are presented.