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The synthesis of a new {Ni8} cluster bearing tetrazolate- and azido-bridging ligands, and supported by chelating α-methyl-2-pyridine-methanol (mpmH) groups, is described herein. The reported compound has a unique trapezoidal prismatic topology, resulting from an unexpected in situ click reaction between the MeCN reaction solvent and the N3- ions under mild, room-temperature conditions. Such a click chemistry approach to the preparation of 0-D compounds is relatively unexplored and represents a fruitful strategy for the synthesis of new coordination clusters and molecule-based magnetic materials.

The synthesis of a new {Ni8} cluster bearing tetrazolate- and azido-bridging ligands, and supported by chelating α-methyl-2-pyridine-methanol (mpmH) groups, is described herein. The reported compound has a unique trapezoidal prismatic topology, resulting from an unexpected in situ click reaction between the MeCN reaction solvent and the N3- ions under mild, room-temperature conditions. Such a click chemistry approach to the preparation of 0-D compounds is relatively unexplored and represents a fruitful strategy for the synthesis of new coordination clusters and molecule-based magnetic materials.

The germylone dimNHCGe (5, dimNHC=diimino N‐heterocyclic carbene) undergoes a [2+2] cycloaddition with isocyanates RNCO (R=4‐tolyl or 3,5‐xylyl) to furnish novel alkyl carboxamido germylenes 7 (R=4‐tolyl) and 8 (R=3,5‐xylyl), featuring a C−C bond between the former carbene carbon and the isocyanate moiety. Heating a mixture of 8 with 4‐tolyl isocyanate to 100 °C results in isocyanate metathesis, demonstrating reversible C−C bond formation on the reduced germanium compound. DFT calculations suggest that this process occurs via the reductive dissociation of isocyanate from 8 that regenerates the parent Ge(0) compound 5. [ABSTRACT FROM AUTHOR]

Reaction of NacNacGa with phenylisocyante generates a transient species amenable to unusual 1,3-C–H bond addition of unactivated sp3 C–H and sp2 C–H bonds of substrates featuring a hard donor atom. This reaction proceeds for pyridine oxide, dimethylsulfoxide, and dimethylacetamide, but not for pyridine, cyclohexanone, and ethyl acetate. C–H activation was also not observed for reactions with triethylphosphine oxide but, interestingly, in the presence of this compound isocyanate undergoes self-coupling on Ga(I) with a regioselectivity that is different when carried out in the absence of Et3PO. [ABSTRACT FROM AUTHOR]

Dye-sensitized/organic solar cells (DS/O-SCs) have gradually improved their power conversion efficiencies (PCEs) and are now being considered for commercialization. This comprehensive review focuses on a prominent class of small organic molecules called triphenylamines (TPAs), which are extensively utilized in DS/O-SCs due to their low cost and facile synthestic procedures. Specifically, we aim to explore state-of-the-art experimental strategies for synthesizing TPA derivatives as efficient sensitizers. These sensitizers have demonstrated the ability to significantly enhance the PCE of DS/O-SCs by over 10%. The insights gained from this review will contribute to advancing the rational design of TPA-based DS/O-SCs, paving the way for potential commercial applications in the near future. [ABSTRACT FROM AUTHOR]

Diimino−carbene‐supported germylone dimNHCGe does not react with BPh3 and does not activate dihydrogen in the FLP mode in the combination with this borane. However, it reacts with B(C6F5)3 to give the zwitterionic borate dimNHCGe−(C6F4)BF(C6F5)2. This compound can be converted into the hydroborate dimNHCGe−(C6F4)BH(C6F5)2 (8) and further into [dimNHCGe−(C6F4)B(C6F5)2]+ (4). Compound 4 is a Ge/B analogue of Stephan's FLP parent P/B compound (C6H2Me3)2P−C6F4−B(C6F5)2 but unlike the latter cannot split dihydrogen. Moreover, attempts to prepare a Ge/B analogue of the zwitterion (C6H2Me3)2HP−C6F4−BH(C6F5)2 by protonation of borate 8 resulted in immediate elimination of H2. [ABSTRACT FROM AUTHOR]

A 1,1'‐disubstituted ferrocenyl pyrroloimidazolone with syn stereochemistry undergoes double lithiation–electrophile quench in a one‐pot procedure to give C2‐symmetric 1,1',2,2'‐tetrasubstituted products in >95 : 5 diastereomeric ratio (dr). These results represent an extension of double lithiation to access tetrasubstituted planar chiral ferrocenes for the first time to a nitrogen‐linked (pyrroloimidazolone) chiral directing group. The stereochemistry of the products was determined by X‐ray crystallography of distannane and dibromide adducts in combination with deuteration, elimination, and transmetalation experiments. Results support that products arise from selective deprotonation of the pro‐Sp position of each cyclopentadienyl (Cp) ring. [ABSTRACT FROM AUTHOR]

Reactions of silicon and germanium dichlorides L⋅ECl2 (E=Si, L=IPr; E=Ge, L=dioxane) with the phosphinoamidinato‐supported disilylene ({κ2(N,P)‐NNP}Si)2 resulted in formal tetrylene insertions into the Si−Si bond. In the case of the reaction with silylene, two products were isolated. The first product ({κ2(N,P)‐NNP}Si)2SiCl2, is the formal product of direct SiCl2 insertion into the Si−Si bond of ({κ2(N,P)‐NNP}Si)2 and thus features two separated silylamido silylene centers. Over time, migration of the SiCl2 group to a lateral position afforded the second product, the disilylene {κ2(Si,P)−SiCl2NNP}Si−Si{κ2(N,P)‐NNP}. In contrast, insertion of GeCl2 resulted only in the isolation of the germanium analogue of {κ2(Si,P)−SiCl2NNP}Si−Si{κ2(N,P)‐NNP}, containing a Ge atom in the central position namely, compound {κ2(Si,P)−SiCl2NNP}Ge−Si{κ2(N,P)‐NNP}, which is a rare example of a silylene‐germylene. Finally, reaction of disilylene ({κ2(N,P)−NNP}Si)2 with SiCl4 and SiHCl3 led to the formation of the new bis(silyl)silylene, ({NNP}SiCl2)2Si:. All four new products from these insertion reactions have been characterized by multinuclear NMR and single‐crystal X‐ray diffraction studies. [ABSTRACT FROM AUTHOR]

The synthesis and structural and magnetic characterization of a new tridentate 2,2'-bipyridine dicarboxamide ligand obtained from 3,3'-diamino-2,2'-bi-pyridine and 2-pyridine carbonyl chloride is presented.

The syntheses and characterization of two tetrathiafulvalene (TTF) derivatives bearing pyridine-based substituents and 1,5'-dimethyl-6-oxoverdazyl radicals are described. Although several organic donor radicals, which carry a stable radical unit, are reported, this is the first for which the PI-donor is TTF and the pi-radical is verdazyl.