Vinylphosphonium and 2-aminovinylphosphonium salts – preparation and applications in organic synthesis

Abstract

The main synthetic routes towards vinylphosphonium salts and their wide applications in organic synthesis are discussed in this review. Particular attention is paid to the use of these compounds as building blocks for the synthesis of carbo- and heterocyclic systems after their prior transformation into the corresponding phosphorus ylides, followed by the intramolecular Wittig reaction with various types of nucleophiles containing a carbonyl function in their structures.

Consecutive reactions to construct tricarbonyl compounds and synthetic applications thereof

“…After proving the efficiency of the cascade process, we investigated the possibility of performing annulations via intramolecular condensation reactions. Thus, when 14b was treated with NaH in THF at rt, followed by the addition of triphenylvinylphosphonium bromide (Schweizer's reagent) 19 no reaction was observed. If the reaction mixture was heated under reflux, several spots are observed on TLC.…”

Four‐Selective Pyridine Alkylation via Wittig Olefination of Dearomatized Pyridylphosphonium Ylides

“…The Wittig olefination is one of the most frequently used reactions to construct carbon‐carbon bonds and typically uses phosphonium salts adjacent to sp 3 ‐hybridized carbon atoms as coupling partners with a vast array of aldehydes and ketones [1] . This process extends to sp 2 ‐hybridized systems where nucleophilic addition to vinylphosphonium salts generates the key ylide intermediate [2] . However, applying the same logic to arenes is less conceivable because of the energetic penalty of disrupting all‐carbon aromatic systems.…”

Photoinduced Hydrophosphination of Terminal Alkynes with Tri(o-tolyl)phosphine: Synthesis of Alkenylphosphonium Salts

“…Alkenylphosphonium salts serve as unique and versatile building blocks . A cationic phosphonium moiety withdraws π-electrons from the C–C double bond, which takes part in various reactions with electron-rich partners.…”