C−F Bond Activation Mediated by Phosphorus Compounds

Abstract

The activation and functionalization of CÀFb onds has garnered significant attention in the scientificc ommunity as as trategy to mitigate toxicitya nd environmental concerns, as well as provide new pathways to agro-and pharmaceuticalc hemicals and materials. Although severalt ransition-metal-based systemsh ave been developed for this transformation,t he use of main-group compoundsr emains less explored. In recent years, several strategies for CÀF bond activation have focused on the use of phosphorusbased reagents. In this Minireview,a no verview of strategies is provided that exploits P V andP III -based Lewis acids as well as P III Lewis bases in frustrated Lewis pair (FLP) protocols for hydrodefluorination, CÀCc ouplings andC ÀFd erivatizations.

Mechanistic Features in Al(I)-Mediated Oxidative Addition of Aryl C–F Bonds: Insights From Density Functional Theory Calculations

“…Our previous studies show that the aluminum center of NacNacAl (1), as the N-heterocyclic carbene (NHC) analog, has similar electronic characters with the transition metal (Zhang and Cao, 2016). Although the C–F bond activation by the main-group element centers has been investigated, both experimentally (Meier and Braun, 2009; Caputo et al, 2013; Stahl et al, 2013; Chen et al, 2017; Bayne and Stephan, 2019; Pait et al, 2019) and theoretically (Mondal et al, 2017), the detailed mechanisms for the oxidative addition of C–F bonds at the Al(I) of NacNacAl (1) are still largely unknown. Herein, we have performed extensive density functional theory (DFT) calculations on the C–F bond activation, and the possible mechanisms for the diversity of oxidative addition reactions and dependence of the ease of C–F oxidative addition on the fluorination and position have been explored.…”

Catalysis, FLPs, and Beyond

“…P(V) and P(III) Lewis acids effect the hydrosilylation of a variety of substrates, as well as the deoxygenation of ketones and the arylation of benzyl fluorides and alkyl and aryl CF 3 derivatives. 56 The ability of FLPs to stoichiometrically capture CO 2 has also evolved to catalytic reductions of CO 2 to CO and phosphine oxide, and the catalytic hydroboration of CO 2 provides methoxy-boranes, a source of methanol. 57 In related heterogeneous work, the concept of FLPs has been extended to surface FLPs, in which hydroxylated indium oxide converts CO 2 and H 2 to CO and H 2 O.…”

Main Group Catalysis: Cationic Si(II) and Ge(II) Compounds as Catalysts in Organosilicon Chemistry

“…The oxidative coupling of hydridosil(ox)anes which is catalyzed by the Cp-coordinated cationic Si(II) and Ge(II) compounds 1 and 2 (Scheme 13) however, is a further anhydrous alternative which avoids safety issues [17]. In this procedure, aldehydes are used as oxidants for Si-H groups which are themselves reduced to ethers.…”

“…In order to move towards sustainable and environmentally friendly catalyst systems, attractive candidates would be the lighter p-block compounds. In the last decade, Lewis-acidic compounds based on boron (recent articles and reviews [7][8][9][10]), carbocations (recent articles and reviews [11][12][13][14]), phosphorus(III) and (V) cations (recent articles and reviews [15][16][17][18]), including frustrated Lewis pairs (FLPs) (recent articles and reviews [19][20][21]), have moved into the focus of catalysis.…”