Isocyanate Formation from Reactions of Early Lanthanide Metal Atoms with NO and CO in Solid Argon

Abstract

The reactions of early lanthanide metal atoms (Ce, Pr, and Nd) with carbon monoxide and nitric oxide mixtures are studied by infrared absorption spectroscopy in solid argon. The reaction intermediates and products are identified via isotopic substitution as well as theoretical frequency calculations. The results show that the reactions proceed with the initial formation of inserted NLnO molecules, which subsequently react with CO to form the NLnO(CO) complexes on annealing. The NLnO(CO) complexes further isomerize to the more stable isocyanate OLnNCO species under UV light excitation.

Infrared Spectroscopy and Density Functional Theory Investigations of the Reactivity of Titanium Atoms with Carbon Monoxide and Water Isolated in Solid Argon: Sequential Evolution from Triplet to Singlet State

“…All the experimentally observed vibrational frequencies for various isotopic substitutions as well as corresponding DFT-calculated harmonic wavenumbers and the relative infrared intensities are listed in Tables 2 and 3. The calculated frequency shifts due to the isotopic 12 O confirms the assignments for the Ti−H and Ti−OH stretching modes. On the basis of concentration and annealing effects, we can attribute the band in far-infrared at 330.4 cm −1 to HTiOH−CO.…”

“…In another work, the reactions of early lanthanide metal atoms (Ce, Pr, and Nd) with carbon monoxide and nitric oxide have been investigated. The results show that the reactions proceed with the initial formation of a linear inserted NLnO molecule, which subsequently reacts with CO to form the NLnO­(CO) complex …”

“…The results show that the reactions proceed with the initial formation of a linear inserted NLnO molecule, which subsequently reacts with CO to form the NLnO(CO) complex. 12 Experimental and theoretical investigations have been performed on the reactions of titanium atoms with water exclusively. Using infrared spectroscopy, Kauffman et al showed that thermally evaporated Sc, Ti, and V atoms in solid argon could react spontaneously with water molecules to form the insertion product HMOH.…”

Dicerium letterbox-shaped tetraphenolates: f-block complexes designed for two-electron chemistry

“…41,42 Under certain conditions, praseodymium can exist in the formal Pr IV oxidation state in some solid-state compounds such as NaPrF 5 , 44 PrF 4 , 45 and Pr oxides or even in the +V oxidation state in the gas-phase. [46][47][48][49][50] However, molecular Pr IV complexes remain an elusive and interesting target. Recent reports on the synthesis and isolation of the Tb IV complexes 51,52 have shown great potential for the stabilisation of rare earth metals in the +IV oxidation state with bespoke ligand systems.…”

Probing the Chemical Bond between Lanthanides and Carbon: CeC, PrC, NdC, LuC, and TmC2

“…In 1971, Pimentel and Spratley described the chemistry of the lanthanides, writing that “Lanthanum has only one important oxidation state in aqueous solution, the +3 state. With few exceptions, this tells the whole boring story about the other lanthanides.” Since then, it has been well documented that organometallic complexes containing lanthanides can participate in interesting and exotic chemistries and have the ability to access several oxidation states. − Accordingly, numerous organolanthanide compounds have been studied and characterized using a variety of experimental and computational methodologies. − The bonding schemes between the lanthanide atoms and carbon in these compounds are quite diverse, featuring single and multiple lanthanide–carbon bonds and well-characterized σ-, π-, and backbonding interactions.…”