Bis(amino)cyclopropenium Trifluoroborates: Synthesis, Hydrolytic Stability Studies, and DFT Insights

Abstract

A simple and direct two-step synthesis of bis(amino)cyclopropenium trifluoroborate (BAC-BF) derivatives from readily available reagents is reported. Hydrolysis studies revealed these BAC-BF derivatives were remarkably stable toward defluorination. Notably, this first study of BAC-BF adduct hydrolytic stability establishes the compounds reported herein possess half-lives ( t) exceeding 0.23 × 10 min (∼160 days). Density functional theory (DFT) and quantum theory of atoms in molecules (QTAIM) calculations exploring the basis of this high stability are described.

Selective Aerobic Oxidation of Benzylic Alcohols Catalyzed by a Dicyclopropenylidene–Ag(I) Complex

“…In reflecting upon these previous works and with the intent of expanding the scope of Ag­(I)-catalyzed methodologies targeting selective alcohol oxidations, we envisioned merging the redox activity of Ag­(I) with the strong σ-donor ability of carbene bis­(diisopropyl)­aminocyclopropenylidene (BAC) as a stabilizing ligand to provide dicarbene–Ag­(I) complex [Ag­(BAC) 2 ] + as a catalytic platform for selective alcohol oxidation (Scheme b). In acting upon this concept and furthering our program interest in cyclopropenium and cyclopropenylidene chemistries, herein we report the synthesis and first catalytic application of homoleptic dicarbene–Ag­(I) complex [Ag­(BAC) 2 ]­[CO 2 CF 3 ] ( 1 ). As reported, vide infra dicarbene–Ag­(I) complex 1 catalyzes the selective oxidation of benzylic alcohols to aldehydes or ketones in the presence of abundant atmospheric molecular oxygen as an oxidant and inexpensive base (Scheme c).…”

Cyclopropenium Cationic-Based Covalent Organic Polymer-Enhanced Poly(ethylene oxide) Composite Polymer Electrolyte for All-Solid-State Li–S Battery

“…The cyclopropenium cation is the smallest aromatic structure with a positive charge, and introducing amino groups through an SN 2 reaction can enhance the stability of the triangular framework . The various physical and chemical properties of cyclopropenium cations are obtained by replacing the substituents; , thus, they have been used as ionic liquids, redox-active polymers for redox flow batteries, transfection agents, and other biologically active compounds. , …”

“…The cyclopropenium cation is the smallest aromatic structure with a positive charge, and introducing amino groups through an SN 2 reaction can enhance the stability of the triangular framework. 31 The various physical and chemical properties of cyclopropenium cations are obtained by replacing the substituents; 32,33 thus, they have been used as ionic liquids, 34 redox-active polymers for redox flow batteries, 35 transfection agents, and other biologically active compounds. 36,37 On the basis of above considerations, herein, an aromatic cyclopropenium cationic-based COP with chloride counterions (termed as iCP@Cl) was constructed through a simple condensation reaction and replaced Cl − with TFSI − by ion exchange (termed as iCP@TFSI).…”

Cationic Cyclopropenium-Based Hyper-Crosslinked Polymer Enhanced Polyethylene Oxide Composite Electrolyte for All-Solid-State Li-S Battery

“…The physical and chemical properties of cyclopropane cations are obtained by substitutes [27]. Therefore, they are used as ionic liquids, redox active polymers, and other bioactive compounds [28][29][30]. Our previous work has shown that the cyclopropenium cationic-based polymer electrolyte possesses high conductivity and lower crystallinity [31].…”