Storing redox equivalent in the phenalenyl backbone towards catalytic multi-electron reduction

Abstract

Redox equivalent storage in the phenalenyl backbone towards catalytic multi-electron reduction.

Switching between mono and doubly reduced odd alternant hydrocarbon: designing a redox catalyst

“…Furthermore, this observation of PLY ring dearomatization clearly indicates that the (-CH=CH-) alkene fragment of PLY transforms into alkane (-CH 2 -CH 2 -) fragment upon two electron reduction and addition of 2 H + (from HCl). It may be noted that hydrogen atom abstraction by mono-reduced B-N-B embedded PLY radical has been reported by Wagner and coworkers very recently 37 and the dearomatization of PLY radical by abstraction of a hydride (H + +2e -) has been demonstrated earlier 24 . Such conclusion was also supported by our isotope labelling experiment with DCl and by characterizing the deuterium incorporated product (see SI, Figures S17-21).…”

“…20 Recently, such in situ generated mono-reduced phenalenyl based radicals were reported in designing cathode materials for single component H 2 O 2 fuel cell 21 and in electron transfer catalysis during various organic transformations. [22][23][24][25] Such approach using in-situ generated mono-reduced phenalenyl radicals opens a possibility to bridge between two seemingly dissimilar areas such as spin-electronics and catalysis. 26…”

Transition metal-free catalytic reduction of primary amides using an abnormal NHC based potassium complex: integrating nucleophilicity with Lewis acidic activation

“…Notably, during the formation of N-borylated amide (2a 0 ), evolution of hydrogen gas was monitored which was unambiguously supported by 1 H NMR resonance at d 4.49 ppm (Scheme 3d). 53 Furthermore, a stoichiometric reaction was performed between N-borylated amide (2a 0 ) and KN(SiMe 3 ) 2 to substantiate the role of KN(SiMe 3 ) 2 . The sharp downeld shi of the carbonyl group (by 9.9 ppm) in the 13 C NMR spectra (d 179.1 ppm) compared to its borylated amide, 2a 0 (d 169.2 ppm) (Fig.…”

Mimicking transition metals in borrowing hydrogen from alcohols

“…56 In this regard, we earlier demonstrated that PLY can store and transfer redox equivalents in the form of C-H bonds during multi-electron reduction processes. 57 Very recently, we reported that phenalenyl ligands can be reduced by two electrons and can subsequently trap two protons via dearomatization of one of the phenyl rings of PLY. 58 Such observations 57,58 made us curious whether the PLY moiety can store both hydride and proton together thus imitating the role of a metal in a typical borrowing hydrogen mechanism followed by its transfer for subsequent reduction integrated in a catalytic fashion.…”