Ceric(IV) Ammonium Nitrate Mediated Phosphorylation of Alkenes: Easy Access to (E )-Vinylphosphonates

Photocatalytic C(sp3)-P and C(sp2)-P Bond Formation via a Phosphorus Radical Cation

A straightforward method for the phosphorylation of electron-deficient alkenes and aryl alkynes has been developed, leading to C(sp3)-P and C(sp2)-P bond formation. This process involves the generation of phosphorus radical cation intermediates through the photocatalyzed oxidation of ethyl diarylphosphinites. The coupling with electron-deficient alkenes encompasses a variety of heteroaromatics, including pyridine, (benzo)thiazole, and benzoxazole, as well as α,β-unsaturated esters and amides. Impressively, the coupling of radical cations with aryl alkynes demonstrated remarkable regioselectivity, thereby facilitating the synthesis of rare α-aryl vinyl phosphine oxides.

Bisphosphorylation of anhydrides - convenient access to bisphosphonates with a P-O-C-P motif

A novel strategy of bisphosphorylation of anhydrides with P(O)-H reagents via a DMAP-catalyzed and DBU-promoted process has been developed. These one-step transformations proceed efficiently to provide convenient access to a variety of P-O-C-P motif containing organophosphorus compounds. In addition, the gram-scale synthesis and the efficient recovery of the by-product highlight the sustainability and applicability of this method.

Manganese(I) Catalyzed Alkenylation of Phosphine Oxides Using Alcohols with Liberation of Hydrogen and Water

Herein, a catalytic cross-coupling of methyldiphenylphosphine oxide with arylmethyl alcohols leading to the alkenylphosphine oxides is reported. A manganese pincer catalyst catalyzes the reactions, which provides exclusive formation of trans-alkenylphosphine oxides. Mechanistic studies indicate that reactions proceed via aldehyde intermediacy and the catalyst promotes the C═C bond formation. Reactions are facilitated by dearomatization, and aromatization metal-ligand cooperation operates in catalyst. Use of abundant base metal catalyst and formation of water and H₂ as the only byproducts make this catalytic protocol sustainable and environmentally benign.

Knoevenagel Condensation of Phosphinoylacetic Acids with Aldehydes: An Efficient One-Pot Strategy for the Synthesis of P-Functionalized Alkenyl Compounds

A wide range of commercially available aldehydes have been applied to Knoevenagel condensation reaction to give E-alkenylphosphine oxides and vinylphosphine oxides. The readily available phosphinoylacetic acids derived from P(O)–H compounds were used as the starting materials in the reaction, providing a highly stereoselective and efficient method for constructing α,β-unsaturated phosphine oxides. Moreover, this simple and practical procedure provides an alternative and more environmentally friendly synthesis strategy for this type of P-functionalized alkenyl compounds.

Transition metal-free and regioselective vinylation of phosphine oxides and H-phosphinates with VBX reagents

A series of phosphine oxides and H-phosphinates were vinylated in the presence of the iodine(iii) reagents vinylbenziodoxolones (VBX), providing the corresponding alk-1-enyl phosphine oxides and alk-1-enyl phosphinates in good yields with complete chemo- and regioselectivity. The vinylation proceeds in open flask under mild and transition metal-free conditions.