A nickel complex was found to be capable of stepwise reducing nitrate to dinitrogen gas using carbon monoxide as the reaction partner.

Two pathways of alkoxide migration occurring at a nickel(II) center supported by a PPP ligand (PPP = P[2-PPr-CH]) are presented in this Article. In the first route, the addition of a π-acidic ligand to a (PPP)Ni alkoxide species reveals the formation of a P-O bond. This reaction occurs via metal-ligand cooperation (MLC) involving a 2-electron reduction at nickel. To demonstrate a P-O bond formation, a nickel(II) isopropoxide species (PPP)Ni(OPr) (4) was prepared. Upon addition of a π-acidic isocyanide ligand CNBu, a nickel(0) isocyanide species (PPP)Ni(CNBu) (6b) was generated; P-O bond formation occurred via reductive elimination (RE). When CO is present, migratory insertion (MI) occurs instead. The reaction of 4 with CO(g) results in the formation of (PPP)Ni(COOPr) (5), representing an alternative pathway. The corresponding RE product (PPP)Ni(CO) (6a) can be independently produced from the substitution reaction of {(PPP)Ni}(μ-N) (3) with CO(g). While two different carbonylation pathways in 4 seem feasible, C-O bond forming migratory insertion singly occurs. Regeneration of a (PPP)Ni moiety via a P-O bond cleavage was demonstrated by treating 3 with CO(g). The formation of (PPP)Ni(OCOOPr) (7) clearly shows that an isopropoxide group migrates onto the bound CO ligand, and a P-Ni moiety is regenerated.

Nitrogen oxide (NO x ) conversion is an important process for balancing the global nitrogen cycle. Distinct from the biological NO x transformation, we have devised a synthetic approach to this issue by utilizing a bifunctional metal catalyst for producing value-added products from NO x . Here, we present a novel catalysis based on a Ni pincer system, effectively converting Ni−NO x to Ni−NO via deoxygenation with CO(g). This is followed by transfer of the in situ generated nitroso group to organic substrates, which favorably occurs at the flattened Ni(I)−NO site via its nucleophilic reaction. Successful catalytic production of oximes from benzyl halides using NaNO 2 is presented with a turnover number of >200 under mild conditions. In a key step of the catalysis, a nickel(I)− • NO species effectively activates alkyl halides, which is carefully evaluated by both experimental and theoretical methods. Our nickel catalyst effectively fulfills a dual purpose, namely, deoxygenating NO x anions and catalyzing C−N coupling. Article pubs.acs.org/JACS

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EUV lithography has been one of the key factors that enables the continuation of semiconductor scaling beyond N7. While it is a vital technique for the HVM of the most recent advanced logic and DRAM devices, the EUVL still needs more efforts in order to fully exploit its capability and extend the application. One particular aspect that has been considered as of critical importance is the optical/chemical stochastic effects which may cause L/S, contact pattern defects limiting the efficiency of EUVL. The simplest way to alleviate the stochastic effects is to employ the higher EUV exposure dose; however, this approach is impractical as it obviously leads to even lower productivity. In this work, the alternative chemicals -such as EUV PTD developer and NTD rinse which are specifically prepared to overcome the stochastic effects -are examined to enhance the performance efficiency of EUVL. The focused features that thoroughly explored are EUV dose, local CD uniformity, PR swelling, pattern collapse, and defects. It is found that, with the chemical composition modification of developer and rinse, EUV pattern fidelity can be effectively optimized resulting in extended process window and improved productivity. It is expected that this work would not only facilitate the extension of EUV application but also help understand how EUV resists behave when they are under the influence of ancillaries.