Anastasiya O. Korocheva

One-pot microwave synthesis of tertiary phosphine sulfides directly from aromatic alkenes, elemental phosphorus and sulfur in KOH–DMSO system

Aromatic alkenes (vinylbenzene, 1-(tert-butyl)-4-vinylbenzene, 1-chloro-4-vinylbenzene) react with red phosphorus and elemental sulfur in the superbasic system KOH–DMSO(H2O) under microwave irradiation (600 W, 6–8 min, Ar) in the presence of hydroquinone to afford tris(2-phenylethyl)-, tris[2-(4-tBu-phenyl)ethyl]- and tris[2-(4-Cl-phenyl)ethyl]phosphine sulfides in 53%, 38% and 42% yield, respectively. GRAPHICAL ABSTRACT

First example of the \( C_{sp^2 } \)-P bond formation in the reaction of red phosphorus with hetaryl halides

Direct reactions of red and white phosphorus with electrophiles (aryland hetarylalkenes, arylacetylenes, alkyl, allyl, and benzyl halides) in superbasic systems alkali metal hydroxide – dipolar aprotic solvent (DMSO, HMPTA) or under the conditions of phase transfer catalysis are now considered as a novel chlorine-free method of formation of the С–P bond [1, 2]. Within this approach, the one-pot methods have been elaborated for the synthesis of various phosphines, phosphine oxides, and phospinic acids [1, 2] which had earlier been obtained by multistep processes from phosphorus halides. However, in the case of the substitution reaction only the Сsp3–P bond was formed. Recently, tris(1-naphthyl)phosphine was synthesized from red phosphorus and 1-naphthyl bromide in the system KОН–DMSO [3]. To the best of our knowledge, there are no data in the literature on the formation of the Сsp2–P in the reactions of elemental phosphorus with hetaryl halides in superbasic systems.

Nucleophilic addition of phosphine to 4-chlorostyrenes in the KOH-DMSO system

In the superbasic system KOH-DMSO (H2O) at 60–75 °C (2–2.5 h, atmospheric pressure), 4-chlorostyrene and 4-chloro-α-methylstyrene add phosphine at the double bond to form 1: 1 and 2: 1 anti-Markovnikov adducts in 10–18% and 58–67% yields, respectively.

Synthesis of tris(2-pyridyl)phosphine from red phosphorus and 2-bromopyridine in the CsF-NaOH-DMSO superbasic system

164 Pyridylphosphines are widely used as polydentate chemolabile P,N ligands for the design of multipur pose metal complex catalysts [1–3], highly reactive building blocks in organic synthesis [4], and precur sors in the preparation of new pharmaceuticals [5, 6]. Among pyridylphosphines, tris(2 pyridyl)phosphine is of special interest as a tripodal ligand of chelating type due to the geminal arrangement of the nitrogen atoms with respect to the phosphorus atom. Metal complexes obtained from tris(2 pyridyl)phosphine are efficient catalysts for industrially important processes, such as alkene hydroformylation [7], ethylene poly merization [8], methoxycarbonylation of acetylenes [9], and diene synthesis [10].

Novel atom-economic synthesis of thioselenophosphinates via three-component reaction between secondary phosphine sulfides, elemental selenium, and amines

An efficient, general, and atom-economic synthesis of organoammonium thioselenophosphinates has been developed by exploiting a three-component reaction between secondary phosphine sulfides, elemental selenium, and various amines. The reaction proceeds under mild conditions (70–75 °C, 1 h, EtOH) to afford thioselenophosphinates in 77–94% yields.

The Direct Phosphorylation Of 2-, 3-, and 4-Methylstyrenes and 2,4,6-Trimethylstyrene with Elemental Phosphorus VIA Trofimov–Gusarova Reaction

GRAPHICAL ABSTRACT Abstract 3- and 4-Methylstyrenes react with red phosphorus in the superbase system KOH/DMSO (110 °C, 2 h) to afford tertiary phosphine oxides in 20–25% total yield. Under microwave irradiation (600 W) this reaction proceeds for 5 min giving in the case of 2-, 3-, and 4-methylstyrenes mixtures of tris[2-(methylphenyl)ethyl]phosphines and their oxides. Subsequent treatment of these products with H2O2 (acetone/H2O, r.t., 5 min) allowed the phosphine oxides to be isolated in 45–68% yields. 2,4,6-Trimethylstyrene reacts with red phosphorus (KOH/DMSO 600 W, 5 min) in a similar manner to furnish tris[2-(2,4,6-trimethylphenyl)ethyl]-phosphine oxide (40% yield) along with 2-(2,4,6-trimethylphenyl)ethylphosphinic acid (21% yield).

Direct phosphorylation of β-alkylstyrenes with elemental phosphorus under Trofimov-Gusarova reaction conditions

In the past decades, the Trofimov–Gusarova reaction of red phosphorus with electrophilic reagents in heterogeneous strongly basic media, e.g., in a system alkali metal hydroxide–polar aprotic solvent (DMSO, HMPA) or under conditions of phase-transfer catalysis, has been successfully developed and opened new prospects in chlorine-free and environmentally acceptable syntheses of previously unknown or difficultly accessible organic phosphines, phosphine oxides, and phosphonic and phosphinic acids [1–3]. Alkenes (styrenes [4], 1H-indene [5], allylbenzenes [6], vinylpyridines [7]), alkynes [8, 9], and alkyl [10], allyl [11], benzyl [12], aryl [13], and hetaryl halides [14] were used as electrophiles in these reactions. We recently showed that 1-methoxy-2-[(E)-prop-1-en-1-yl]benzene reacts with red phosphorus in KOH–DMSO to give 2-(2-methoxyphenyl)-1-methylethylphosphinic acid in 63% yield [15].