Umpolung catalyzed by organophosphines: efficient β,β-dimerization of vinylphosphonates affording linear dimers

A salt-free synthesis of 1,2-bisphosphorylethanes via an efficient PMe3-catalyzed addition of >P(O)H to vinylphosphoryl compounds

“…However, since trimethylphosphine can easily add to a vinylphosphoryl compound to generate a phosphonium intermediate 4, 19 we consider that this catalytic reaction should take place via a cycle as shown in Scheme 2. Thus, the phosphonium intermediate 4, generated by the addition of PMe 3 to 3, was protonated by 2, and PMe 3 was substituted by the nucleophilic >P(O) moiety.…”

Phosphonium Phenolate Zwitterion vs Phosphonium Ylide: Synthesis, Characterization and Reactivity Study of a Trimethylphosphonium Phenolate Zwitterion

“…[1,2] For example, lipophilic carboxylate phosphabetaines (I, Y = CO 2 , Scheme 1a) as analogs of organic amino acids are endowed with a wide range of chemical and biological properties, [3] and have found valuable applications in cellar biology. [7] On contrast, phosphonium zwitterions of type II in which the cationic phosphonium and anionic centre are linked by aromatic rings receive limited attentions and have been be sparsely studied (Scheme 1b). [7] On contrast, phosphonium zwitterions of type II in which the cationic phosphonium and anionic centre are linked by aromatic rings receive limited attentions and have been be sparsely studied (Scheme 1b).…”

“…[4] In organic chemistry, beside as synthetic reagents, [5] phosphonium zwitterions are frequently engaged as reactive intermediates in catalytic reactions, particularly in those involving nucleophilic addition of phosphines to electron-deficient unsaturated systems, [6] and several intermediates have been reported with fair stability for characterization. [7] On contrast, phosphonium zwitterions of type II in which the cationic phosphonium and anionic centre are linked by aromatic rings receive limited attentions and have been be sparsely studied (Scheme 1b). [8][9][10] Specifically, only few examples of triarylphosphonium phenolate zwitterions (Y = O, R = Ph, Scheme 1b) have been reported, [8] and particularly little is known on their alkyl analogs (Y = O, R = alkyl, Scheme 1b).…”

Mizoroki–Heck Reaction of Aryl Halides and Dialkyl Allylphosphonates in Water Catalyzed by Reusable Palladium Nanoparticles

“…These aryl‐substituted allylphosphonates are obtained by the reaction of substituted cinnamyl halides or alcohols with trialkyl phosphites; however, most of the corresponding halides and alcohols have to be prepared via multistep syntheses. Wittig reagents and vinylphosphonates have also been applied to react with aldehydes, giving aryl‐substituted allylphosphonates …”