2022

Antiaromaticity-Promoted Radical Anion stability in α-vinyl Heterocyclics

As an electron-rich species, radical anions have a wide range of applications in organic synthesis. In addition, aromaticity is an essential concept in chemistry that has attracted considerable attention from experimentalists and theoreticians. However, it remains unknown whether there is a relationship between aromaticity and thermodynamic stability of a radical anion. In this work, we demonstrate that the thermodynamically stable radical anions could be formed by the corresponding antiaromatic neutral species through density functional theory calculations.

Predicting Dinitrogen Activation by Five-Electron Boron-Centered Radicals

Due to the high bond dissociation energy (945 kJ mol–1) and the large highest occupied molecular orbital–lowest unoccupied molecular orbital (HOMO–LUMO) gap (10.8 eV), dinitrogen activation under mild conditions is extremely challenging. On the other hand, the conventional Haber–Bosch ammonia synthesis under harsh conditions consumes more than 1% of the world’s annual energy supply. Thus, it is important and urgent to develop an alternative approach for dinitrogen activation under mild conditions.

Computational predictions of adaptive aromaticity for the design of singlet fission materials

Singlet fission has attracted extensive attention from experimentalists and theoreticians due to its ability to improve photovoltaic conversion efficiency. Still, designing singlet fission materials remains challenging. In this work, we explored the relationship between adaptive aromaticity and singlet fission potentials by computationally screening the adaptive aromatic species reported by our group.

Aromaticity-promoted CS2 Activation by Heterocycle-Bridged P/N-FLPs: A Comparative DFT Study with CO2 Capture

Carbon dioxide (CO2) capture has attracted considerable attention from both experimental and theoretical chemists. In comparison, Carbon disulfide (CS2) activation is less developed. Here, we carry out a thorough comparative density functional theory study to examine the reaction mechanisms of CS2 activation by five-membered heterocycles-bridged P/N frustrated Lewis pairs (FLPs).

A Conjugated Figure-of-eight Oligoparaphenylene Nanohoop with Adaptive Cavities Derived from Cyclooctatetrathiophene Core

A fully conjugated figure-of-eight nanohoop is presented with facile synthesis. The molecule’s lemniscular skeleton features the combination of two strained oligoparaphenylene loops and a flexible cyclooctatetrathiophene core. Its rigid yet guest-adaptive cavities enable the formation of the peanut-like 1:2 host-guest complexes with C 60 or C 70 , which have been confirmed by X-ray crystallography and characterized in solution.

A Genuine Stannylone with a Monoatomic Two-Coordinate Tin(0) Atom Supported by a Bis(silylene) Ligand

The monoatomic zero-valent tin complex (stannylone) {[Si II (Xant)Si II ]Sn 0 } 5 stabilized by a bis(silylene)xanthene ligand, [Si II (Xant)Si II = PhC(N t Bu) 2 Si(Xant)Si(N t Bu) 2 CPh], and its bis-tetracarbonyliron complex {[Si II (Xant)Si II ]Sn 0 [Fe(CO) 4 ] 2 } 4 are reported. The stannylone 5 bearing a two-coordinate zero-valent tin atom is synthesized by reduction of the precursor 4 with potassium graphite.

[(CrGe9)Cr2(CO)13]4−: A disubstituted case of ten-vertex closo cluster with spherical aromaticity

We report the first disubstituted hetero-ten-vertex closo cluster [(CrGe9)Cr2(CO)13]4- with three adjacent Cr(CO)n units adopting both η5 and η1 coordination modes, which was synthesized through the reaction of “KGe1.67” with (MeCN)3Cr(CO)3 and Cr(CO)6 in ethylenediamine (en) solution. In contrast to the η1-Cr atoms forming localized two-center two-elelctron (2c-2e) Cr-Ge bonds, the hetero atom η5-Cr exhibits versatile bonding mechanisms including three 5c-2e and five 8c-2e delocalized bonds which account for Hückel aromaticity.

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