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Trifluoromethyl cationic carbyne (CF3C+:) possessing dual carbene‐carbocation behavior emulated as trifluoromethyl metal‐carbynoid (CF3C+=M) has not been explored yet, and its reaction characteristics are unknown. Herein, a novel α‐diazotrifluoroethyl sulfonium salt was prepared and used in Rh‐catalyzed three‐component [2+1+2] cycloadditions for the first time with commercially available N‐fused heteroarenes and nitriles, yielding a series of imidazo[1,5‐a] N‐heterocycles that are of interest in medicinal chemistry, in which the insertion of trifluoromethyl Rh‐carbynoid (CF3C+=Rh) into C=N bonds of N‐fused heteroarenes was involved. This strategy demonstrates synthetic applications in late‐stage modification of pharmaceuticals, construction of CD3‐containing N‐heterocycles, gram‐scale experiments, and synthesis of phosphodiesterase 10A inhibitor analog. These highly valuable and modifiable imidazo[1,5‐a] N‐heterocycles exhibit good antitumor activity in vitro, thus demonstrating their potential applications in medicinal chemistry. [ABSTRACT FROM AUTHOR]

Precisely introducing topological defects is an important strategy in nanographene crystal engineering because defects can tune π‐electronic structures and control molecular assemblies. The synergistic control of the synthesis and assembly of nanographenes by embedding the topological defects to afford two‐dimensional (2D) crystals on surfaces is still a great challenge. By in‐situ embedding ladder bipyrazinylene (LBPy) into acene, the narrowest nanographene with zigzag edges, we have achieved the precise preparation of 2D nonbenzenoid heteroacene crystals on Au(111). Through intramolecular electrocyclization of o‐diisocyanides and Au adatom‐directed [2+2] cycloaddition, the nonbenzenoid heteroacene products are produced with high chemoselectivity, and lead to the molecular 2D assembly via LBPy‐derived interlocking hydrogen bonds. Using bond‐resolved scanning tunneling microscopy, we determined the atomic structures of the nonbenzenoid heteroacene product and diverse organometallic intermediates. The tunneling spectroscopy measurements revealed the electronic structure of the nonbenzenoid heteroacene, which is supported by density functional theory (DFT) calculations. The observed distinct organometallic intermediates during progression annealing combined with DFT calculations demonstrated that LBPy formation proceeds via electrocyclization of o‐diisocyanides, trapping of heteroarynes by Au adatoms, and stepwise elimination of Au adatoms. [ABSTRACT FROM AUTHOR]

Satoh–Miura reaction is an important method for extending π‐systems by forging multi‐substituted benzene rings via double aryl C−H activation and annulation with alkynes. However, the development of highly enantioselective Satoh–Miura reaction remains rather challenging. Herein, we report an asymmetric Satoh–Miura reaction between 1‐aryl benzo[h]isoquinolines and internal alkynes enabled by a SCpRh‐catalyst. Judiciously choosing the counteranion of the Rh‐catalyst is crucial for the desired reactivity over the competitive formation of azoniahelicenes. Detailed mechanistic studies support the proposal of counteranion‐directed switching of reaction pathways in Rh‐catalyzed asymmetric C−H activation. [ABSTRACT FROM AUTHOR]

Despite the advances in the area of catalytic alkene hydrosilylation, the enantioselective hydrosilylation of alkenes bearing a heteroatom substituent is scarce. Here we report a rhodium‐catalyzed hydrosilylation of β,β‐disubstituted enamides to directly afford valuable α‐aminosilanes in a highly regio‐, diastereo‐, and enantioselective manner. Stereodivergent synthesis could be achieved by regulating substrate geometry and ligand configuration to generate all the possible stereoisomers in high enantio‐purity. [ABSTRACT FROM AUTHOR]

Materials showing synergy of magnetic and dielectric transitions are promising candidates for future molecular devices. The challenge is how to realize synergy between spin and dielectric transitions with responses to external stimuli. Herein, we design a 2D spin crossover (SCO) complex, [FeII(dpa)][(pzTp)FeIII(CN)3]2 (1) (dpa=1,2‐bis(4‐pyridyl)ethyne and pzTp=tetrakis(pyrazolyl)borate). The local structural changes about the FeII ion were propagated to the whole crystal through the rigid bridging ligands (dpa), leading to elastic interactions to realize the abrupt SCO and rotational movements of polar apical pyrazolyl rings in the [(pzTp)FeIII(CN)3]− units. Dielectric measurements confirmed a substantial dielectric change (Δϵ′=2.3) upon the spin transition. This work provides a rational strategy to couple the spin transition and rotation of polar components, which is crucial for the synergetic switch of magnetism and dielectricity. [ABSTRACT FROM AUTHOR]

A series of solid supramolecules based on acrylamide–phenylpyridium copolymers with various substituent groups (P−R: R=−CN, −CO2Et, −Me, −CF3) and cucurbit[7]uril (CB[7]) are constructed to exhibit tunable second‐level (from 0.9 s to 2.2 s) room‐temperature phosphorescence (RTP) in the amorphous state. Compared with other solid supramolecules P−R/CB[7] (R=−CN, −CO2Et, −Me), P−CF3/CB[7] displays the longest lifetime (2.2 s), which is probably attributed to the fluorophilic interaction of cucurbiturils leading to a uncommon host–guest interaction between 4‐phenylpyridium with −CF3 and CB[7]. Furthermore, the RTP solid supramolecular assembly (donors) can further react with organic dyes Eosin Y or SR101 (acceptors) to form ternary supramolecular systems featuring ultralong phosphorescence energy transfer (PpET) and visible delayed fluorescence (yellow for EY at 568 nm and red for SR101 at 620 nm). Significantly, the ultralong multicolor PpET supramolecular assembly can be further applied in fields of anti‐counterfeiting and information encryption and painting. [ABSTRACT FROM AUTHOR]

Room‐temperature thermoelectric materials are the key to miniaturizing refrigeration equipment and have great scientific and social implications, yet their application is hindered by their extreme scarcity. BiTe exhibiting strong spin‐orbit coupling peaks ZT at 600 K. Herein, we discover the synergy effect of Sb doping in BiTe that eliminates the detrimental band inversion and leads to an overlap of conduction band (CB) and valence band that significantly increases the S from 33 to 124 μV K−1. In addition, this effect enhances the μ from 58 to 92 cm2 V−1 s−1 owing to the sharp increase in the CB slope along the Γ‐A in the first Brillouin zone. Furthermore, Sb doping increases the anharmonicity, shortens the phonon lifetime and lowers κlat. Finally, Se/Sb codoping further optimizes the ZT to 0.6 at 300 K, suggesting that Bi0.6Sb0.4Te1−ySey is a potential room‐temperature TE material. [ABSTRACT FROM AUTHOR]

Direct asymmetric functionalization of the inert α C−H bonds of N‐unprotected propargylic amines is a big challenge in organic chemistry, due to the low acidity (pKa≈42.6) of the α C−H bonds and interruption of the nucleophilic NH2 group. By using a chiral pyridoxal as carbonyl catalyst, we have successfully realized direct asymmetric α‐C−H addition of N‐unprotected propargylic amines to trifluoromethyl ketones, producing a broad range of chiral alkynyl β‐aminoalcohols in 54–84 % yields with excellent stereoselectivities (up to 20 : 1 dr and 99 % ee). The α C−H bonds of propargylic amines are greatly activated by the pyridoxal catalyst via the formation of an imine intermediate, resulting in the increase of acidity by up to 1022 times (from pKa 42.6 to pKa 20.1), which become acidic enough to be deprotonated under mild conditions for the asymmetric addition. This work presented an impressive example for asymmetric functionalization of inert C−H bonds enabled by an organocatalyst. [ABSTRACT FROM AUTHOR]

Owing to the strong nucleophilicity of the NH2 group, free‐NH2 glycinates react with MBH acetates to usually deliver N‐allylated products even in the absence of catalysts. Without protection of the NH2 group, chiral pyridoxal catalysts bearing an amide side chain at the C3 position of the naphthyl ring switched the chemoselectivity of the glycinates from intrinsic N‐allylation to α‐C allylation. The reaction formed chiral multisubstituted glutamic acid esters as SN2′–SN2′ products in good yields with excellent stereoselectivity (up to 86 % yield, >20 : 1 dr, 97 % ee). As compared to pyridoxal catalysts bearing an amide side arm at the C2 position, the pyridoxals in this study have a bigger catalytic cavity to enable effective activation of larger electrophiles, such as MBH acetates and related intermediates. The reaction is proposed to proceed via a cooperative bifunctional catalysis pathway, which accounts for the high level of diastereo‐ and enantiocontrol of the pyridoxal catalysts. [ABSTRACT FROM AUTHOR]

Uncontrolled growth of Zn dendrites and side reactions are the major restrictions for the commercialization of Zn metal anodes. Herein, we develop a TiOx/Zn/N‐doped carbon inverse opal (denoted as TZNC IO) host to regulate the Zn deposition. Amorphous TiOx and Zn/N‐doped carbon can serve as the zincophilic nucleation sites to prevent the parasitic reactions. More importantly, the highly ordered IO host homogenizes the local current density and electric field to stabilize Zn deposition. Furthermore, the three‐dimensional open networks could regulate Zn ion flux to enable stable cycling performance at large current densities. Owing to the abundant zincophilic sites and the open structure, granular Zn deposits could be realized. As expected, the TZNC IO host guarantees the steady Zn plating/stripping with a long‐term stability over 450 h at the current density of 1 mA cm−2. As a proof‐of‐concept demonstration, a TZNC@Zn||V2O5 full cell shows long lifespan over 2000 cycles at 5.0 A g−1. [ABSTRACT FROM AUTHOR]