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An efficient base-catalyzed double addition of H-phosphine oxides to alkynes is developed. In the presence of a catalytic amount of a base, the addition of various H-phosphine oxides to both aromatic and aliphatic alkynes took place efficiently to produce the corresponding bisphosphoryl compounds in excellent yields. This method provides an easy direct way to prepare bisphosphine oxides that are of high importance in organic synthesis.

A Pd-catalyzed dehydrogenative phosphorylation of thiols is developed. A variety of thiols dehydrogenatively couple readily with all three kinds of P(O)–H compounds, i.e., H-phosphonates, H-phosphinates, and secondary phosphine oxides, providing a general access to the valuable phosphorothioates including the P-chiral compounds. A plausible mechanism is proposed.

The nickel-catalyzed α-benzylation of sulfones with readily available benzylic alcohol derivatives was achieved via C–O activation. The transformation was complete in 30 minutes using a simple Ni(COD)2 as a catalyst without any additional ligands. A variety of substituted sulfones including the building block for bioactive compound eletriptan were synthesized by using the strategy.

Optically active α-hydroxyphosphinates with both C- and P-stereogenic centers are obtained by rhodium- or iridium-catalyzed substrate-directed stereoselective addition of the optically pure H-phosphinates to aldehydes. The reaction most probably proceeds by a transition-metal-catalyzed mechanism with hydridometal complexes as key intermediates in the catalytic cycle.

An efficient nickel-catalyzed phosphorylation of phenol derivatives with P(O)-H compounds via C-O/P-H cross-coupling is described. Under the reaction conditions, various phenyl pivalates coupled readily with hydrogen phosphoryl compounds to afford the corresponding coupling products aryl phosphonates and aryl phosphine oxides in good to high yields.

Various α-benzylated arylacetonitriles are prepared under mild conditions by Ni-catalyzed direct cross-coupling reactions of benzylic alcohol derivatives with arylacetonitriles via C—O activation.

An efficient Ni-catalyzed synthesis of (E)-olefins using the readily available benzylic alcohol derivatives and arylacetonitriles is described. This transformation should proceed via a tandem process involving nickel-catalyzed cross coupling via C-O activation and subsequent stereoselective E2 elimination.

Review: recent progress in the preparation of organo-phosphorus compounds via transitin metal-catalyzed dehydrogenative couplings of P(O)H compounds; 79 refs.

Diaryl disulfides such as (PhS)2 are useful organocatalysts for the photolytic addition of bis(pinacolato)diboron to terminal alkynes.

Chloroform replaces the highly toxic CCl4 as halogenating reagent and solvent in Atherton—Todd-type reactions of alcohols and thiols with secondary phosphine oxides.

A convenient and versatile method was developed for the preparation of 1,2-bisphosphorylethanes. Thus, in the presence of a catalytic amount of trimethylphosphine, a variety of >P(O)H compounds efficiently add to vinylphosphoryl compounds to produce the corresponding 1,2-bisphosphorylethanes in high yields. In most cases, the trimethylphosphine catalyst was simply removed under vacuum leaving spectroscopically pure adducts. The present method provided a halogen and metal-free clean process for the preparation of 1,2-bisphosphorylethanes.

P,C-stereogenic α-hydroxyl phosphinates or phosphine oxides are synthesized in stability-controlled diastereoselective reactions catalyzed by bases in up to

Arylphosphine oxides (III) and (V) as well as arylphosphines (VII) are readily prepared by a Ni-catalyzed cross-coupling of aryl nitriles with the corresponding P—H compounds.

In this account, we summarize our recent work on the preparation of optically active H-phosphinates and their stereospecific transformations, including regio- and stereospecific additions, nucleophilic substitutions with organolithiums and Grignard reagents, halogenation with copper(II) chloride, and dehydrogenative couplings with heteroatom–hydrogen bonds. These reactions provide efficient ways for the synthesis of valuable, optically active, P-stereogenic, organophosphorus compounds from relatively easily prepared, enantiomerically pure, menthyl hydrogen phosphinates. The applications of optically active H-phosphinates in catalytic asymmetric hydrogenations are also discussed. 1 Optically Pure Menthyl Hydrogen Phosphinates: Easily Accessible P-Stereogenic Starting Materials 2 Optically Pure Menthyl Hydrogen Phosphinates as Starting Materials for the Synthesis of P-Chiral Compounds 2.1 Stereospecific Additions 2.1.1 Additions to Alkynes 2.1.2 Addition to Alkenes 2.1.3 Addition to p-Quinones 2.1.4 Additions to Ketones or Aldehydes 2.2 Stereospecific Nucleophilic Substitution by Organolithiums or Grignard Reagents 2.3 Stereospecific Halogenation with Copper(II) Chloride 2.4 Stereospecific Cross-Dehydrogenative Coupling with Nucleo­philes (Amines, Alcohols, Thiols, etc.) 2.5 Stereospecific Cross-Coupling with C–X Bonds 3 Asymmetric Catalytic Hydrogenation Reactions with Optically Pure Menthyl Hydrogen Phosphinates as Ligands 4 Conclusion

An efficient strategy is developed which allows the preparation of various types of phosphorus compounds from pivalates and different P—H reagents.

The Ni-catalyzed direct C–H/C–O cross couplings of benzylic alcohol derivatives with fluorobenzenes and heteroarenes are disclosed. This transformation provides a straightforward and efficient method for the synthesis of these valuable heteroatom-containing compounds.

P,C-Stereogenic 1,3-bisphosphinylpropanes [(III) and (V)] are stereoselectively synthesized from (Rp)-methylphenylphosphine oxide (II) and unsaturated aldehydes [(I) and (IV)] following a 1,2-addition/1,3′-phosphorus migration sequence.

Catalyst-free and selective C–N bond functionalization has been achieved through three-component coupling of amines, dihalomethane, and >P(O)H species. This reaction takes place stereospecifically with retention of configuration at phosphorus, which can produce various new optically active phosphorus analogues of α-amino acids.

The atom-efficient one-pot synthesis succeeds using aromatic aldehydes and aromatic conjugated aldehydes, but fails using the corresponding aliphatic compounds or ketones.

A copper-catalyzed aerobic oxidative amidation reaction of inert C-C bonds with tertiary amines has been developed for the synthesis of tertiary amides, which are significant units in many natural products, pharmaceuticals, and fine chemicals. This method combines C-C bond activation, C-N bond cleavage, and C-H bond oxygenation in a one-pot protocol, using molecular oxygen as the sole oxidant without any additional ligands.

A copper-catalyzed system for the amidation of carboxylic acids with tert-amines through C–N bond cleavage was developed. This protocol is practical and represents a simple way to produce functionalized amides from basic starting materials in moderate to good yields. A plausible mechanism is proposed for the reaction.

A combination of dibromomethane and dimethylaniline as reagents is employed as source of HBr for the hydrobromination of alkynes to afford the Markovnikov-type vinyl bromides in good yields.

An efficient synthesis of 2-hetarylquinazolin-4(3H)-ones via copper-catalyzed direct aerobic oxidative amination of sp3C–H bonds has been developed. This tandem oxidation–amination–cyclization transformation represents a straightforward protocol to prepare 2-hetaryl-substituted quinazolinones from easily available 2-aminobenzamides and (2-azaaryl)methanes.

The immobilized catalyst can be easily recovered from the reaction mixture via simple centrifugal separation and reused several times without severe deactivation.

Copper-catalyzed stereospecific oxidative dehydrocouplings of P(O)–H bonds with amines under air took place efficiently at room temperature to afford the corresponding amidophosphorus compounds in ...

An air-stable, simple (R(P))-mentylbenzylphosphinate, readily available in large quantities, can efficiently induce the rhodium-catalyzed asymmetric hydrogenation of α-acetamidocinnamates with high enantioselectivity (up to 99.6% ee). Intramolecular hydrogen bonding plays an important role in this asymmetric induction.

The optimized conditions allow the selective semihydrogenation of a broad range of terminal aromatic and aliphatic alkynes to afford the corresponding alkenes in high yields.

A facile Ni-catalyzed semihydrogenation of internal alkynes to ( E )-alkenes using the cheap and easily handled hypophosphorous acid as a hydrogen donor was described. This reaction is featured by high reaction efficiency to produce the corresponding ( E )-alkenes selectively.

A simple, efficient and highly functional group compatible method for the synthesis of propargylamines from terminal alkynes, dichloromethane and tertiary amines using silver catalysts has been developed.

The stereochemistry of H-phosphinates with different nucleophiles (amines, alcohols, phenols, and mercaptanes) under Atherton—Todd reaction conditions is investigated.

A highly selective head-to-tail dimerization of aliphatic and aromatic alkynes (I) and (III) is reported.

Organophosphorus compounds are of high importance in organic synthesis, catalysis, biochemistry, pharmaceuticals, and material science. In this mini review, we summarize our recent studies on transition metal-catalyzed green and atom efficient transformations of P(O)-H bonds to various versatile organophosphorus compounds, including the highly regio- and stereoselective P(O)-H additions to carbon-carbon unsaturated compounds, asymmetric hydrophosphorylation reactions, and dehydrogenative coupling reactions of P(O)-H compounds with carbon-H and heteroatom-H compounds. These new reactions provide efficient, general and practical ways for the preparation of a variety of well-defined functional organophosphorus compounds. Mechanistic aspects related to the catalytic processes are also discussed.

C- and O-phosphoryl hydroquinone derivatives are prepared selectively by employing different additives.

The catalytic hydrogenation of alkynes such as (I) with formic acid can be controlled by changing the conditions to selectively produce (Z)-alkenes such as (II), (E)-alkenes such as (III), or alkanes such as (IV).

The title reaction leads to the compounds (III), (VI), (VIII), and (X) and suppresses the competing olefin polymerization.

Complexes derived from the new, stable oxapalladacycle OPC are found to be more efficient and selective catalysts for addition reactions of H-heteroatom compounds to alkynes than the common Pd-complexes used so far.

A new and general methodology for the introduction of a phosphorus functionality to the internal carbon of a terminal alkyne is developed.

The reaction of H-phosphinates and secondary phosphine oxides with amines and alcohols proceeds highly stereospecifically to give the corresponding coupling products with inversion of configuration at the phosphorus center under the Atherton−Todd reaction conditions. This finding leads to the establishment of a general and efficient method for the synthesis of a variety of optically active organophosphorus acid derivatives from the easily available chiral H-phosphinates and secondary phosphine oxides.

β-Trichlorotelluro ketones 4 generated in situ from siloxyclopropanes 1 and TeCl 4 react with dimethyl sulfoxide or some amines under mild conditions to provide the corresponding α-methylene ketones 3 in good yields.

The addition of diorganyl tellurides (PhTePri and nBuTeBut) to phenylacetylene took place efficiently via a radical mechanism with a perfect regioselectivity to give corresponding vinyl tellurides. The E isomer was formed exclusively in the case of nBuTeBut, whereas PhTePri gave a E/Z mixture.

Diphenyl ditelluride (phTeTePh) adds to a variety of acetylenes upon irradiation with visible light in the absence of solvent to provide vic-bis(phenyltelluro)alkenes in good yields. The reaction may proceed by a radical-chain mechanism that includes the addition to acetylenes of phenyltelluro radical (PhTe e ) generated in situ by photolysis of diphenyl ditelluride, followed by the S H 2 reaction between thus formed β-(phenyltelluro)alkenyl radicals and diphenyl ditelluride. In the cases of unactivated acetylenes such as 1-octyne, the addition proceeds stereoselectively to provide only (E)-vic-bis(phenyltelluro)alkenes. Contrary to this, activated acetylenes like phenylacetylene give rise to a mixture of E- and Z-isomers of vic-bis(phenyltelluro)alkenes. Since the obtained vic-bis(phenyltelluro)alkenes indicate absorption in the near-UV, irradiation with near-UV light in solvent causes a novel reverse reaction of the adducts to the starting acetylenes and diphenyl ditelluride. Accordingly, irradiation with visible light (>400 nm) under high concentrations of the substrates induces the addition of (PhTe) 2 to acetylenes, whereas irradiation with near-ultraviolet (>300 nm) under dilution condition causes the reverse reaction.

Alkenes react with NO2 and (PhSe)2 with the evolution of NO to afford high yields of β-(phenylseleno)alkyl nitrates which are easily hydrolysed to the corresponding β-hydroxyalkyl selenides.

Oxidative addition of Ph2P(O)H to M(PEt3)3 (M = Pd, Pt) readily took place at room temperature in benzene to afford cis-MH[P(O)Ph2][PPh2(OH)](PEt3) complexes. The structure of the platinum complex ...

One drop is enough to switch from hydropalladation to phosphinylpalladation. If one drop of diphenylphosphinic acid is added for the hydrophosphinylation of alkynes with diphenylphosphane oxide, there is a reversal in regioselectivity (as shown below).