Trinuclear cyclopentadienylniobium carbonyls are of interest since Cp3Nb3(CO)7 (Cp=eta5-C5H5) is a stable molecule having a unique face-bridging carbonyl group formally donating six electrons to the Nb3 triangle through one Nb-C sigma-bond and two orthogonal pi-bonds. In this connection, the molecules Cp3Nb3(CO)n (n=9, 8, 7, 6) have been examined by density functional theory. The saturated deri...

Carbon-carbon bond cleavage/functionalization is synthetically valuable, and selective carbonyl-C(sp3 ) bond cleavage/alkynylation presents a new perspective in constructing ynamides, ynoates, and ynones. Reported here is the first alkoxyl-radical-enabled carbonyl-C(sp3 ) bond cleavage/alkynylation reaction by photoredox catalysis. The use of novel cyclic iodine(III) reagents are essential for ...

Rhenium complex, [ReBr(CO)3(thf)]2-catalyzed reactions between aromatic imines and either acetylenes or α,β-unsaturated carbonyl compounds gave indene derivatives in good to excellent yields. These reactions proceed via C–H bond activation, insertion of acetylenes or α,β-unsaturated carbonyl compounds, intramolecular nucleophilic cyclization, and reductive elimination. Indene derivatives were a...

Key Points Fire  Elemental nickel dust and nickel carbonyl are flammable  Nickel is incompatible with acids, oxidizing agents and sulphur  Nickel and nickel carbonyl react violently with oxidants  Nickel and nickel compounds emit toxic fumes and vapours of nickel carbonyl when heated to decomposition  In the event of a fire involving nickel carbonyl, use fine water spray and gas tight kit ...

Al2(HPO4)3 was easily prepared and used as a solid acid in acetalization of carbonyl compounds at room temperature and under solvent-free conditions. The protection was done in short reaction times and in good to high isolated yields. The cheapness and availability of this reagent with easy procedure and work-up make this method attractive for the organic synthesis. Keywords—Acetalization, acid...

Natural availability of carbonyl groups offers reductive carbonyl coupling tremendous synthetic potential for efficient olefin synthesis, yet the catalytic carbonyl cross-coupling remains largely elusive. We report herein such a reaction, mediated by hydrazine under ruthenium(ii) catalysis. This method enables facile and selective cross-couplings of two unsymmetrical carbonyl compounds in eithe...

Equilibria between carbonyl compounds and their enamines (from O-TBDPS-derived prolinol) have been examined by NMR spectroscopy in DMSO-d(6). By comparing the exchange reactions between pairs (enamine A + carbonyl B → carbonyl A + enamine B), a quite general scale of the tendency of carbonyl groups to form enamines has been established. Aldehydes quickly give enamines that are relatively more s...

The asymmetric unit of the title compound, [RuCl(2)(C(13)H(9)N(3))(CO)(2)], consists of four crystallographically independent Ru(II) complexes. Each Ru(II) atom is in a distorted octa-hedral environment coordinated by two carbonyl ligands, two Cl atoms and a chelating 2-(2-pyrid-yl)-1,8-naphthyridine (pynp) ligand. The carbonyl ligands are cis to each other, while the Cl atoms are trans. Relati...

A sensitive liquid chromatograph/tandem mass spectrometric technique (LC/MS/MS) was applied to determine aliphatic and aromatic carbonyl compounds in ambient air. Traces of the carbonyl compounds were sampled by passing through a Sep-Pak DNPH-silica cartridge. Their derivatives were thus eluted with acetonitrile, separated by reversed-phase liquid chromatography and determined by quadrupole tan...

Carbonyl-carbonyl interactions between adjacent backbone amides have been implicated in the conformational stability of proteins. By combining experimental and computational approaches, we show that relevant amidic carbonyl groups associate through an n→π* donor-acceptor interaction with an energy of at least 0.27 kcal/mol. The n→π* interaction between two thioamides is 3-fold stronger than bet...