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The reaction of potassium 2-t-Bu-germabenzenide, in which the anionic carbon atom of phenyl anion is replaced with a germanium atom, with benzil resulted in the 1:2 reaction to give a unique penta-coordinated germanate having a 1,3,2-dioxagermole skeleton. This clearly reflects the characteristics of the germabenzenide as a divalent germanium species.

Interactions between gold‐based materials and dioxygen (O2) have motivated researchers to understand reaction mechanisms for O2 activation by homo‐ and heterogeneous gold catalysts. In this work, gold(I) porphyrin dinuclear complexes were synthesized with a saddle‐distorted porphyrin ligand. The gold(I) porphyrin complexes showed unprecedented O2 activation in the presence of protic solvents to form gold(III) tetradentate porphyrin complexes. Mechanistic insights into the O2 activation by the gold(I) center were elucidated by spectroscopic measurements and theoretical calculations, revealing that dissociation of halides on the gold(I) center by alcohol solvents and hydrogen bonding of an N−H proton in the distorted porphyrin with dioxygen played important roles in establishing the unique reactivities of gold(I) complexes. [ABSTRACT FROM AUTHOR]

The synthesis, isolation, and characterization of 1‐adamantylaminogermylene 1 have been achieved utilizing kinetic stabilization with a bulky aryl group on the germanium atom. Aminogermylene 1 was found to be stable in toluene solution at 110 °C for 3 days without decomposition. The chalcogenation reaction of 1 aiming to synthesize heavy amides gave the head‐to‐tail type dimers of the corresponding heavy amides. [ABSTRACT FROM AUTHOR]

In order to synthesize a silabenzenyl anion, in which the anionic carbon atom of a phenyl anion was replaced with a silicon atom, the reductive dearylation reaction of 1‐Tbt‐2‐tert‐butyl‐silabenzene (Tbt=2,4,6‐tris[bis(trimethylsilyl)methyl]phenyl) with KC8 was attempted. Unexpectedly, this reaction resulted in the formation of a dianion species without the elimination of the Tbt group. This is totally different from the reactions of Tbt‐substituted germa‐ or stannabenzene with KC8, which resulted in the formation of the corresponding heavy analogues of phenyl anion, together with the elimination of Tbt group. Experimental and theoretical investigation revealed that one of the protons of the o‐benzyl positions of the Tbt group was abstracted by the negatively charged silicon atom of an in‐situ generated intermediate. Compared with the previously reported germanium system, the contrasting results indicate that the central heavy group 14 element has a great influence on the elimination step of the Tbt group. [ABSTRACT FROM AUTHOR]

Ligand exchange reactions of 9-sila- and 9-germa-phenathrenes with chromium carbonyl complexes, [Cr[(C[H.sub.3]CN).sub.3][(CO).sub.3]] and [Cr([η.sup.6]-benzene)[(CO).sub.3]], were performed. Their reactions with [Cr[(C[H.sub.3]CN).sub.3][(CO).sub.3]] afforded the corresponding [η.sup.6]-complexes, in which Cr[(CO).sub.3] moieties coordinated to the [C.sub.6]-rings. However, those with [Cr([η.sup.6]-benzene) [(CO).sub.3]] gave unique four-membered complexes bearing semibridging carbonyl ligands. All the structures of novel complexes were determined by NMR and X-ray crystallographic analysis. Key words: silicon, germanium, chromium, metalla-aromatic compounds, coordination. Des reactions d'echange des ligands 9-silaphenanthrene et 9-germaphenanthrene avec les complexes chrome-carbonyle [Cr[(C[H.sub.3]CN).sub.3][(CO).sub.3]] et [Cr([η.sup.6]-benzene)[(CO).sub.3]] ont ete realisees. La reaction de ces ligands avec le complexe [Cr[(C[H.sub.3]CN).sub.3][(CO).sub.3]] a permis la formation des [η.sup.6]-complexes correspondants, dans lesquels les groupes fonctionnels Cr[(CO).sub.3] sont coordonnes avec les cycles a six carbones ([C.sub.6]). La reaction de ces memes ligands avec [Cr([η.sup.6]-benzene)[(CO).sub.3]], a produit quant a elle des complexes uniques a quatre membres, qui portent des ligands carbonyles semi-pontants. Toutes les structures des nouveaux complexes ont ete determinees pas RMN et cristallographie aux rayons X. [Traduit par la Redaction] Mots-cles: silicium, germanium, chrome, composes organiques metalliques, coordination., Introduction The chemistry of aromatic compounds containing (a) heavier group 14 element(s) (Si, Ge, Sn, and (or) Pb), which we call, 'metalla-aromatic compounds', has dramatically progressed in the last decade. [...]

Mono‐alkene‐inserted [n]cycloparaphenylenes 1 [(ene)‐[n]CPP] with n=6, 8, and 10, mono‐ortho‐phenylene‐inserted [6]CPP 2, and di‐alkene‐insertved [n]CPP 3 [(ene)2‐[n]CPP] with n=4, 6, and 8 were synthesized by fusing CPP precursors and alkene or ortho‐ phenylene groups through coupling reactions. Single‐crystal X‐ray diffraction analyses reveal that the strips formed by the π‐surfaces of 1 and 2 exhibited a Möbius topology in the solid state. While the Möbius topology in the parent 1 and 2 in solution was lost due to the free rotation of the paraphenylene unit even at low temperatures, ene‐[6]CPP 4 with eight 1‐pyrrolyl groups preserved the Möbius topology even in solution. Despite a twist, 1 has in‐plane conjugation and possesses a unique size dependence of the electronic properties: namely, the opposite size dependency of the HOMO–LUMO energy relative to conventional π‐conjugated molecules. [ABSTRACT FROM AUTHOR]