Polymerization-induced emission: a chemical route for uniting nonluminescent monomers into luminescent polymers.

The Kumada cross-coupling reaction of a variety of unactivated aryl chlorides, vinyl chlorides, and heteroaryl chlorides catalyzed by nickel(II) complexes containing pyridine-functionalized NHC ligands is described. The catalysts are so active that the reactions proceed at room temperature in excellent yields.

A family of tetra-, penta-, and hexacoordinate nickel complexes of functionalized N-heterocyclic carbene (NHC) ligands have been prepared via carbene transfer reactions of Ni(PPh3)2Cl2 and silver-NHC complexes in situ generated from corresponding imidazolium salts and Ag2O. These nickel(II) complexes have been characterized by 1H NMR, 13CNMR, and ESI spectroscopy and X-ray diffraction analysis. Structural analysis revealed that [Ni(L1)3](PF6)2 (L1 = 3-butyl-1-(5,7-dimethyl-1,8-naphthyridin-2-yl)imidazolylidene, 3) is a rare example of a nickel complex with trigonal-bipyramidal geometry. [Ni(L4)2](PF6)2 (L4 = 1-butyl-3-((7-methyl-1,8-naphthyridin-2-yl)methyl)imidazolylidene, 5) and [Ni(L20)2](PF6)2 (L20 = 3-(pyridin-2-ylmethyl)-1-(pyrimidin-2-yl)imidazolylidene, 21) are normal square-planar. [Ni(L8)3](PF6)2 (L8 = 3-methyl-1-(pyrimidin-2-yl)imidazolylidene, 9), [Ni(L10)2(CH3CN)](PF6)2 (L10 = 3-ethyl-1-(pyrimidin-2-yl)imidazol-ylidene, 11), [Ni(L12)2(CH3CN)](PF6)2 (L12 = 3-butyl-1-(pyrimidin-2-yl)imidazolylidene, 13), [Ni(L14)2(CH3CN)](PF6)2 (L14 = 3-benzyl-1-(pyrimidin-2-yl)imidazolylidene, 15), and [Ni(L16)2(CH3CN)](PF6)2 (L16 = 3-isopropyl-1-(pyrimidin-2-yl)imidazolylidene, 17) are pentacoordinate, displaying unusual square-pyramidal geometry. [Ni(L12)3](PF6)2 (L9 = 3-butyl-1-(pyrimidin-2-yl)imidazolylid-ene, 19), [Ni(L22)2(CH3CN)2](PF6)2 (L22 = 3-(2,6-diisopropylphenyl)-1-(pyrimidin-2-yl)imidazolylidene, 23), and [Ni(L24)(CH3CN)(H2O)] (L22 = 3-(2,4,6-trimethylphenyl)-1-(pyrimidin-2-yl)imidazolylidene, 25) are octahedral complexes. The structural diversity of these nickel(II) complexes originating from steric pressure of the ligands is discussed.

Chimeras have been used to study the transmission of genetic material and the resulting genetic variation. In this study, two chimeras, TCC and TTC (where the origin of the outer, middle, and inner cell layers, respectively, of the shoot apical meristem is designated by a ‘T’ for tuber mustard and ‘C’ for red cabbage), as well as their asexual and sexual progeny, were used to analyse the mechanism and the inheritance of the variation induced by grafting. Asexual TCC progeny were obtained by adventitious shoot regeneration, while TTC sexual progeny were produced by self-crossing. This study observed similar morphological variations in both the asexual and sexual progeny, including changes in leaf shape and the pattern of shoot apical meristem termination. The leaf shape variation was stable, while the rate of shoot apical meristem termination in the TTC progenies decreased from 74.52% to 3.01% after three successive rounds of self-crossing. Specific red cabbage small RNAs were found in the asexually regenerated plants (rTTT) that were not present in TTT, indicating that small RNAs might be transmitted from red cabbage to tuber mustard during grafting. Moreover, in parallel with the variations in phenotype observed in the progeny, some conserved miRNAs were differentially expressed in rTTT and TTT, which correlated with changes in expression of their target genes. These results suggest that the change in small RNA expression induced by grafting may be an important factor for introducing graft-induced genetic variations, providing a basis for further investigating the mechanism of graft-induced genetic variation through epigenetics.

A nickel-catalyzed thiolation of unactivated C(sp(2))-H bonds with disulfides employing the PIP directing group was described. This process uses a catalytic nickel catalyst and no metallic oxidants or cocatalysts are required. The reaction tolerates various important functional groups and heteroarenes, providing an efficient synthetic pathway to access diverse diaryl sulfides.

Ni(II)-catalyzed ortho-arylation of aromatic and heteroaromatic carboxamides with triethoxy(aryl)silanes assisted by a removable bidentate auxiliary is reported. This transformation features a broad substrate scope, good functional group tolerance, and compatibility with heterocyclic substrates. Compared to the well-established Ni(II)-catalyzed C-H arylation with ArX or aryliodonium salts via oxidative addition, this reaction proceeded via a fluoride-promoted transmetalation.

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Abies beshanzuensis, an extremely rare and critically endangered plant with only three wild adult trees globally, is strongly mycorrhizal-dependent, leading to difficulties in protection and artificial breeding without symbiosis. Root hair morphogenesis plays an important role in the survival of mycorrhizal symbionts. Due to the lack of an effective genome and transcriptome of A. beshanzuensis, the molecular signals involved in the root hair development remain unknown, which hinders its endangered mechanism analysis and protection. Herein, transcriptomes of radicles with root hair (RH1) and without root hair (RH0) from A. beshanzuensis in vitro plantlets were primarily established. Functional annotation and differentially expressed gene (DEG) analysis showed that the two phenotypes have highly differentially expressed gene clusters. Transcriptome divergence identified hormone and sugar signaling primarily involved in root hair morphogenesis of A. beshanzuensis. Weighted correlation network analysis (WGCNA) coupled with quantitative real-time PCR (qRT-PCR) found that two hormone–sucrose–root hair modules were linked by IAA17, and SUS was positioned in the center of the regulation network, co-expressed with SRK2E in hormone transduction and key genes related to root hair morphogenesis. Our results contribute to better understanding of the molecular mechanisms of root hair development and offer new insights into deciphering the survival mechanism of A. beshanzuensis and other endangered species, utilizing root hair as a compensatory strategy instead of poor mycorrhizal growth.