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Two types of Sm(II) complexes bearing either an N-phosphine oxide-substituted imidazolylidene (PoxIm) or the corresponding imidazolinylidene (SPoxIm) were successfully prepared and characterized using single-crystal X-ray diffraction analysis. The general formula of the structures of the complexes was found to be [(anti-[kappa]-O-(S)PoxIm).sub.n]Sm[X.sub.2][(THF).sub.m] where X = I, n = 2, and m = 2 or X = pentamethylcyclopentadienyl, n = 1, and m = 0. The carbene carbon atoms remained intact in these complexes. In some cases, axial chirality was clearly induced around the N-P bonds due to the restricted rotation of the N-phosphinoyl moieties, which arises from the formation of N-phosphinoyl oxygen--Sm(II) bonds. This work highlights a rare example of complexation-induced N-P axial chirality and new aspects regarding lanthanide complexes of multifunctional multipurpose carbenes. Key words: samarium, N-heterocyclic carbenes, axial chirality, phosphine oxide, Introduction Over the past decades, N-heterocyclic carbenes (NHCs) have been widely applied as ligands in organometallic chemistry, (1,2) organocatalysts, (3) and Lewis bases for the stabilization of reactive main group [...]

Perfluoroalkyl substances (PFAS) have been recognized as environmental pollutants. Hence, their efficient and mild destruction is a significant research interest. While many research articles and review papers have reported the cleavage of the C(sp2)−F bonds, single C(sp3)−F bond, and CF3 groups in PFAS, in this study, limited and emerging examples of a longer perfluoroalkyl group containing at least one repeating unit of 1,1,2,2‐tetrafluoroethylene was focused. In this Concept, we summarized recent progress on the chemical defluorination of PFAS via the cleavage of unactivated C(sp3)−F bonds in longer perfluoroalkyl groups under mild conditions (~150 °C). In addition to classical reductive defluorination, strategies featuring Lewis acid activation and the transient generation of an unsaturated bond were described. [ABSTRACT FROM AUTHOR]

1 H NMR (400 MHz, C 6 D 6): = 7.78 [t, 4 J H, F = 7.0 Hz, 3 H, Ar- H), 0.26 (s, 54 H, Si(C H 3) 3 ]. Keywords: triarylboranes; Lewis acids; frustrated Lewis pairs; hydrogenation; boron catalysis; hydrogen separation EN triarylboranes Lewis acids frustrated Lewis pairs hydrogenation boron catalysis hydrogen separation 2187 2192 6 10/31/23 20231127 NES 231127 Graph Triarylboranes are representative Lewis acids that are widely applied as catalysts, activators, sensors, and bioimaging agents. The formation of Et SB 3 sb P=O- B B I SP n sp i b was also confirmed by using SP 11 sp B NMR spectroscopy, and resonances that indicate the generation of four-coordinate boron species were observed at SB B sb = -0.4 ( B B SP 1 sp b ), -0.3 ( B B SP 2 sp b ), and -1.4 ( B B SP 3 sp b ). The NCIs between the individual I meta i -TMS groups probably play a critical role in enhancing the global and effective Lewis acidity of B B SP 1 sp b with respect to B B SP 2 sp b . [Extracted from the article]

SP 1 sp H NMR (300 MHz, acetone- I d i SB 6 sb ): = 11.66 (s, 1 H, H SB N-H sb ), 8.39 (d, I J i = 8.2 Hz, 1 H, H SB 7 sb ), 8.35 (d, I J i = 2.6 Hz, 1 H, H SB 2 sb ), 8.12 (d, I J i = 8.3 Hz, 1 H, H SB 6 sb ). SP 1 sp H NMR (300 MHz, acetone- I d i SB 6 sb ): = 11.49 (s, 1 H, H SB N-H sb ), 8.78 (d, I J i = 2.3 Hz, 1 H, H SB 5 sb ), 8.46 (d, I J i = 2.3 Hz, 1 H, H SB 7 sb ), 8.30 (d, I J i = 2.8 Hz, 1 H, H SB 2 sb ), 8.17-8.07 (m, 2 H, H SB 10or11 sb ), 8.03-7.94 (m, 2 H, H SB 10or11 sb ). SP 13 sp C NMR (75 MHz, acetone- I d i SB 6 sb ): = 157.11 (d, I J i = 15.3 Hz, C SB 4 sb ), 155.38 (dd, I J i = 263.6, 4.4 Hz, Cq), 150.58 (dd, I J i = 253.0, 4.6 Hz, Cq), 148.32 (Cq), 147.54 (C SB 2 sb ), 121.72 (Cq), 120.75 (d, I J i = 3.6 Hz, Cq), 120.03 (Cq), 120.0-104.00 (m, C SB CF sb ). SP 13 sp C NMR (75 MHz, acetone- I d i SB 6 sb ): = 159.44 (C SB 4 sb ), 155.77 (dd, I J i = 266.4, 19.7 Hz, Cq), 150.08 (dd, I J i = 250.8, 15.1 Hz, Cq), 147.14 (C SB 2 sb ), 146.85-146.21 (m, Cq), 122.57-121.48 (m, Cq), 119.05 (dd, I J i = 18.9, 3.4 Hz, C SB 5 sb ), 118.93-114.64 (m, Cq), 119.00-105.00 (m, C SB CF sb ). SP 13 sp C NMR (75 MHz, acetone- I d i SB 6 sb ): = 159.91 (dt, I J i = 252.3, 5.2 Hz, C SB 6 sb ), 157.63 (d, I J i = 3.8 Hz, C SB 4 sb ), 147.42 (Cq), 146.79 (C SB 2 sb ), 133.10 (d, I J i = 7.3 Hz, Cq), 126.29-125.29 (m, C SB 5,7,8 sb ),, 123.00-105.00 (m, C SB CF sb ). [Extracted from the article]

Tetrafluoroethylene (TFE) is an industrial organofluorine feedstock that is used predominantly to fabricate fluorinated polymers. TFE exhibits excellent potential as a building block for synthesizing organofluorine compounds, which are increasingly gaining attention as functional materials, pharmaceuticals, and agrochemicals. In particular, the use of transition-metal complexes in the transformation of TFE is of great interest, considering their widespread use in syntheses of organofluorine compounds over the last few decades. This review highlights studies on the transformation of TFE into organofluorine compounds using transition-metal complexes, except for polymerizations. Our review covers cross-coupling reactions via C–F bond cleavage, fluoroalkylation reactions, multicomponent couplings, and olefin metathesis. 1 Introduction 2 Palladium Complexes 3 Copper Complexes 4 Nickel Complexes 5 Ruthenium Complexes 6 Rhodium Complexes 7 Summary and Perspective [ABSTRACT FROM AUTHOR]

The reversible oxidative cyclization of dienes and aldehydes with nickel(0) has proceeded to provide [eta.sup.3]:[eta.sup.1]-allylalkoxynickel complexes. The results indicate that oxiranes might be potential precursors to their isomeric aldehydes or ketones.

A reaction of eta1-allenyl or eta-propargylpalladium compounds with Pd2(dba)3 was used to synthesize mu-eta3-ellenyl/propargyldipalladium compounds.

It has been possible to show the formation of a new class of complexes indicating a wide range of structures with eta2-type and eta3-type coordination of the alpa,beta-unsaturated compounds, beginning from palladium(O) complex and Lewis acids.