Radical Hydrophosphorylation of Alkynes with R₂P(O)H Generating Alkenylphosphine Oxides: Scope and Limitations

Abstract

Radical hydrophosphorylation of aliphatic terminal alkynes with H-phosphine oxides can produce the corresponding anti-Markovnikov alkenylphosphorus adducts in moderate yields. This method is a cleaner approach for the preparation of the corresponding alkenylphosphine oxides, since it avoids the use of a metal catalyst that sometimes is difficult to remove from the products.

Lewis Acid Enables Ketone Phosphorylation: Synthesis of Alkenyl Phosphonates

“…Recently, Han's group developed a highly efficient route to synthesize vinylphosphonate compounds via palladium‐catalyzed addition reaction of P(O)H compounds to alkynes reaction (Scheme 1). [ 6d,12 ] However, only moderate efficiency was achieved in regio‐ and stereo‐selectivity control from their study. Feng's group [ 13 ] developed a highly efficient synthesis of α‐hydroxy phosphonates via Lewis acid‐catalyzed hydrophosphonylation of ketones with dimethyl phosphonate, which was highly tolerable for functionalized ketones (Scheme 1).…”

Advances in radical phosphorylation from 2016 to 2021

“…Thiocyanodiphenylphosphinoylated compounds could be applied in the development of new bioactive compounds and phosphine-containing ligands. In 2018, Tao et al [75] established the phosphinoyl radical-initiated 1,2-bifunctional thiocyanodiphenylphosphinoylation of alkenes using CuBr 2 as a catalyst and Mn(OAc) 3 as an oxidant, affording a range of thiocyanodiphenylphosphinoylated compounds in reasonable yields [Figure 47]. Mechanistic studies reveal that copper-catalyzed thiocyanation is involved in the reaction.…”

Heterogeneous Catalytic Method for the Copper(II)-Catalysed Addition of H-Phosphinates and Secondary Phosphine Oxides to Phenylacetylene

“…Microwave irradiation has also been used to promote the addition of secondary phosphine oxides to alkynes [35]. Han et al elaborated the metal-free generation of the alkenylphosphorus non-selective anti-Markovnikov adducts under radical conditions [36]. Radical conditions have also been applied for the selective synthesis of Z-alkenylphosphine oxides by Lei and co-workers [37].…”