Catalyst- and Solvent-Free Addition of the P–H Species to Alkenes and Alkynes: A Green Methodology for C–P Bond Formation

Abstract

Traditional methods for C–P bond formation via direct addition of P–H species to unsaturated compounds are usually implemented in the presence of base and metal catalysts or radical initiators in various organic solvents. During the last five years, a novel efficient and general catalyst/initiator- and solvent-free version of the hydrophosphination and hydrophosphinylation of multiple C–C bonds with H-phosphines and their chalcogenides has begun to develop and it is attracting growing attention. This approach corresponds to the recently emerged pot-, atom-, and step-economy (PASE) green paradigm. This review covers the literature on the synthesis of useful and in-demand organophosphorus compounds via catalyst- and solvent-free addition of P–H species to alkenes and alkynes.1 Introduction2 Addition of Secondary Phosphines to Alkenes3 Hydrophosphinylation of Alkenes with Secondary Phosphine Chalcogenides3.1 Oxidative Addition of Phosphine Oxides to Vinyl Sulfides3.2 Addition of Secondary Phosphine Sulfides and Phosphine Selenides to Alkenes3.3 Addition of Secondary Phosphine Sulfides and Phosphine Selenides to Divinyl Chalcogenides3.4 Hydrophosphinylation of Alkenes with Secondary Phosphine/Chalcogen Pair (Three-Component Reactions)4 Addition of Secondary Phosphines to Alkynes5 Addition of Secondary Phosphine Chalcogenides to Alkynes6 Conclusion

N-Heterocyclic Carbene-Coordinated M(II) (M = Yb, Sm, Ca) Bisamides: Expanding the Limits of Intermolecular Alkene Hydrophosphination

“…This reaction offers several advantages such as high atom efficiency and a variety of opportunities for designing complex phosphorous-containing molecules. A series of methods which enable intermolecular hydrophosphination including free radical or UV initiation and acid and superbasic conditions have been developed so far; however, all of them suffer from a lack of selectivity, high waste generation, and the need to use activated substrates. Great progress in hydrophosphination was achieved due to the application of compounds of alkaline- and rare-earth elements as precatalysts, − but the scope of the method is significantly constrained by the limited choice of substrates, both olefin (normally styrenics) and phosphine (ubiquitous PhPH 2 and Ph 2 PH).…”

UV induced hydrophosphination of dimethyl 2-vinylcyclopropane-1,1-dicarboxylate towards phosphine chalcogenides

“…The flask was evacuated and refilled with H 2 (1 atm, balloon) three times. 4 The reaction mixture was heated to reflux at 60 °C and monitored via 31 P{ 1 H} and 1 H NMR spectroscopy. The mixture was then filtered through a pad of Celite.…”

“…In these reports, secondary phosphines, their respective chalcogenides or phosphine–boranes were successfully added to either a series of unactivated olefins, alkynes, aldehydes, ketones, isocyanate and isothiocyanate (Scheme 1). 4 These transformations highlight how simple and straightforward it is to create regioselective anti- Markovnikov organophosphine products. There are no reports of a definitive mechanism for some of these P–H bond additions.…”

Mechanistic Investigation into Single-Electron Oxidative Addition of Single-Atom Cu(I)-N4 Site: Revealing the Cu(I)–Cu(II)–Cu(I) Catalytic Cycle in Photochemical Hydrophosphinylation

“…The hydrophosphinylation of alkenes and alkynes has attracted considerable attention because it is a 100% atom-economic protocol for building versatile organophosphorus compounds. − Over the past decade, hydrophosphinylation has been performed using homogeneous − or heterogeneous catalytic systems, which primarily undergo radical intermediates. ,− In radical hydrophosphinylation, there are two main pathways. ,− , After radical addition between P-centered radicals with alkenes, the alkyl C-centered radical prefers converting to a C–H bond via the hydrogen atom transfer (HAT) process ,,, (Figure a, HAT). Electron-deficient olefins, such as acrylic ester, are generally not compatible; however, the alkenyl C-centered radical often undergoes a SET pathway to the anion (Figure a, SET).…”