The apatite family is a mineral class that also contains the biologically very important hydroxyapatite. Here, we are reporting on the synthesis and characterization of a fully hydride‐substituted strontium apatite, which could be obtained via mechanochemical synthesis and subsequent annealing treatment. The full substitution by hydride anions is proven by various methods, such as neutron powder diffraction of a deuterated sample Sr5(PO4)3D, as well 1H MAS solid state NMR combined with quantum chemical calculations, vibrational spectroscopy and elemental analysis. The present work expands the apatite family from the known halide and hydroxide apatites to the fully hydride‐anion‐substituted variant and is expected to open up a new field of materials containing coexistent phosphate and hydride anions.

Despite major advances, organometallic C-H transformations are dominated by precious 5d and 4d transition metals, such as iridium, palladium and rhodium. In contrast, the unique potential of less toxic Earth-abundant 3d metals has been underexplored. While iron is the most naturally abundant transition metal, its use in oxidative, organometallic C-H activation has faced major limitations due to the need for superstoichiometric amounts of corrosive, cost-intensive DCIB as the sacrificial oxidant. To fully address these restrictions, we describe herein the unprecedented merger of electrosynthesis with iron-catalyzed C-H activation through oxidation-induced reductive elimination. Thus, ferra- and manganaelectro-catalyzed C-H arylations were accomplished at mild reaction temperatures with ample scope by the action of sustainable iron catalysts, employing electricity as a benign oxidant.

The widespread applications of substituted diketopyrrolopyrroles (DPPs) call for the development of efficient methods for their modular assembly. Herein, we present a π-expansion strategy for polyaromatic hydrocarbons (PAHs) by C-H activation in a sustainable fashion. Thus, twofold C-H/N-H activations were accomplished by versatile ruthenium(II)carboxylate catalysis, providing step-economical access to diversely decorated fluorogenic DPPs that was merged with late-stage palladium-catalyzed C-H arylation on the thus-assembled DPP motif.

Well-defined ruthenium(II) biscarboxylate complexes enabled selective ortho-deuteration with weakly-coordinating, synthetically useful carboxylic acid with outstanding levels of isotopic labeling. The robust nature of the catalytic system was reflected by a broad functional group tolerance in an operationallysimple manner, allowing the isotope labeling of challenging pharmaceuticals and bioactive heterocyclic motifs. The synthetic power of our method was highlighted by the selective tritium-labeling of repaglinide, an antidiabetic drug, providing access to defined tritium labeled therapeutics.

Dearomatisation of indole derivatives to the corresponding isatin derivatives has been achieved with the aid of visible light and oxygen. It should be noted that isatin derivatives are highly important for the synthesis of pharmaceuticals and bioactive compounds. Notably, this chemistry works excellently with N-protected and protection-free indoles. Additionally, this methodology can also be applied to dearomatise pyrrole derivatives to generate cyclic imides in a single step. Later this methodology was applied for the synthesis of four pharmaceuticals and a pesticide called dianthalexin B. Detailed mechanistic studies revealed the actual role of oxygen and photocatalyst.

Cationic copper(I) complexes [Cu(aIPrPh)(IPr)]I (3) and [Cu(aIPrPh)2]I (4) featuring an abnormal N-heterocyclic carbene (aNHC) (aIPrPh = 1,3-bis(2,6-diisopropylphenyl)-2-phenylimidazol- 4-ylidene) and/or an NHC (IPr = 1,3-Bis(2,6-diisopropylphenyl)imidazol-2-ylidene) ligand(s) are reported. Treatment of Cu(aIPrPh)I (2) with IPr affords complex 3. Reaction of (IPrPh)I (1) (IPrPh = 1,3-bis(2,6-diisopropylphenyl)-2-phenyl-imidazolium) with CuI in the presence of K{N(SiMe3)2} leads to the formation of 4. Complexes 3 and 4 represent rare examples of mixed aNHC-NHC and bis-aNHC metal complexes, respectively. They are characterized by elemental analysis, NMR spectroscopic, and mass spectrometric studies. The solid-state molecular structures of 3 and 4 have been determined by single crystal X-ray diffraction analyses. The catalytic activity of 2, 3, and 4 has been investigated in the [3+2] cycloaddition of alkynes and organic azides, affording triazole derivatives in an almost quantitative yield. Notably, complexes 2, 3, and 4 are excellent catalysts for the three-fold cycloaddition of a tris-azide with various alkynes. This catalytic protocol offers a high yield access to tris-triazoles in a shorter reaction time and considerably reduces the experimental work-up compared to the classical synthetic method.

Mo complexes are currently the most active catalysts for nitrogen fixation under ambient conditions. In comparison, tungsten platforms are scarcely examined. For active catalysts, the control of N2vs. proton reduction selectivities remains a difficult task. We here present N2 splitting using a tungsten pincer platform, which has been proposed as the key reaction for catalytic nitrogen fixation. Starting from [WCl3(PNP)] (PNP = N(CH2CH2PtBu2)2), the activation of N2 enabled the isolation of the dinitrogen bridged redox series [(N2){WCl(PNP)}2]0/+/2+. Protonation of the neutral complex results either in the formation of a nitride [W(N)Cl(HPNP)]+ or H2 evolution and oxidation of the W2N2 core, respectively, depending on the acid and reaction conditions. Examination of the nitrogen splitting vs. proton reduction selectivity emphasizes the role of hydrogen bonding of the conjugate base with the protonated intermediates and provides guidelines for nitrogen fixation.