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Chiral α-aminophosphonates with adjacent carbon and phosphonate stereogenic centers have been employed as ligands in the copper-catalyzed oxidative coupling of 2-naphthols, resulting in the production of chiral BINOLs in favorable yields and moderate to good enantiomeric excess. This represents the first application of chiral P-based ligands to enable such a transformation. The synthesis of these chiral α-aminophosphonate ligands offers a significant advantage over approaches that typically necessitate elaborate synthetic processes for chiral ligand production.

We have developed a Tf2O-mediated approach for the direct amination of either P(O)–OH or P(O)–H reagents with a variety of aliphatic or aromatic amines. Without the requirement of precious metals and toxic reagents, this protocol provides an alternative route to various phosphinamides and phosphoramides. The reaction proceeds under simple and mild conditions and can be effectively scaled up with similar efficiency.

The traditional methods for the synthesis of phosphinate esters use phosphorus trichloride (PCl3) as the phosphorous source, resulting in procedures that are often highly polluting and energy intensive. The search for an alternative approach that is both mild and environmentally friendly is a challenging, yet highly rewarding task in modern chemistry. Herein, we use an inorganic phosphorous-containing species, NaH2PO2, to serve as the source of phosphorous that participates directly in the nickel-catalyzed selective alkyne hydrophosphonylation reaction. The transformation was achieved in a multicomponent fashion and at room temperature, and most importantly, the H-phosphinate product generated is an advanced intermediate which can be readily converted into diverse phosphinate derivatives, including those bearing new P–C, P–S, P–N, P–Se, and P–O bonds, thus providing a complimentary method to classic phosphinate ester synthesis techniques.

P-Chiral phosphines and sec-phosphine oxides (SPO) are found in a diverse range of compounds that play crucial roles in various fields, including asymmetric catalysis, materials, agrochemistry, and pharmaceutical chemistry. Herein, we describe an enantioselective Ni-catalyzed kinetic resolution of racemic sec-phosphine oxides to obtain the corresponding optically pure P-chiral phosphine oxides and sec-phosphine oxides, respectively. These products are versatile chiral phosphine building blocks that can be used to construct an extensive range of P-chiral phosphines.

An efficient and facile visible-light-mediated tandem difluoromethylation/cyclization of alkenyl aldehydes, with easily accessible and air-stable [Ph3PCF2H]+Br–as the difluoromethylation reagent, has been established. A range of CF2H-substituted chroman-4-one skeletons and their derivatives, such as 2,3-dihydroquinolin-4(1H)-ones, chroman, 3,4-dihydronaphthalen-1(2H)-one, 2,3-dihydrobenzofuran, and 2,3-dihydro-1H-inden-1-one, are efficiently produced in moderate to good yields with excellent chemoselectivity under mild reaction conditions.

A facile and efficient method for the synthesis of primary phosphinamides from Ar2P(O)–H reagents with stable and readily available ammonium carbonate as an ammonia source is disclosed herein for the first time. This ethyl bromoacetate-mediated primary amination proceeds smoothly under mild and simple conditions, without any metal catalyst or oxidant. Moreover, this method is also appropriate for the reaction of Ar2P(O)–H with a variety of amines, alcohols, and phenols to construct P–N or P–O bonds, with features of handy operation, good functional group tolerance, and broad substrate scope.

A novel and selective method of simple copper-salt catalyzed phosphonation of α-amino carbonyl compounds to afford imidoylphosphonates is reported. This reaction system has a broad reaction scope. The convenient and environmentally benign process makes this protocol very attractive.

A new approach to the synthesis of 2-phosphinoylindoles through photoredox catalysis without external oxidants has been developed. Promoted by a ruthenium photoredox catalyst, a broad scope of 2-phosphinoylindoles can be synthesized through phosphinoylation/cyclization of diphenylphosphine oxide at room temperature under irradiation without external oxidants. The estrone skeleton isocyan is also an amenable substrate for this cyclization, yielding a molecule that has potential medicinal applications.

A Tf2O/DMSO-based system for the dehydrogenative coupling of a wide range of alcohols, phenols, thiols, and thiophenols with diverse phosphorus reagents has been developed. This metal- and strong-oxidant-free strategy provides a facile approach to a great variety of organophosphinates and thiophosphates. The simple reaction system, good functional-group tolerance, and broad substrate scope enable the application of this method to the modification of natural products and the direct synthesis of bioactive molecules and flame retardants.

A novel catalytic tautomeric transformation of a β-enaminophosphoryl and 2-aza-Cope rearrangement sequence has been successfully applied to the one-pot synthesis of β-aminophosphonates with high efficiency and good tolerance. In this tandem reaction, Bi(OTf)3exhibits unique activities and promotes both of enamine–imine tautomerism and 2-aza-Cope rearrangement.

With triphenylphosphine oxide serving as both the directing group and the reagent, we have developed a Cp*Ir(III)-catalyzed direct C–H functionalization of triphenylphosphine oxide with 3-diazooxindoles to afford a range of 3-(2-(diphenylphosphoryl)phenyl)indolin-2-one derivatives in moderate to excellent yields. The title products are potentially important building blocks for organic synthesis through various chemical transformations. This protocol is simple and efficient and offers high atom economy with only N2as the byproduct.

The palladium–N-heterocyclic carbene (NHC)-catalyzed allylic alkylation of various pronucleophiles with alkynes has been accomplished under mild conditions. The protocol exhibits broad functional group compatibility and high atom economy. Moreover, the catalytic process avoids the use of external oxidants and acid as additives.

In this work, an efficient palladium-catalyzed Heck-type reaction was successfully used to synthesize a wide range of monoaryl- or diaryl-substituted P-ligands with excellent yields and diastereoselectivity (up to 98% yield, dr >20:1). The preliminary mechanistic studies demonstrated that it possibly underwent a cationic Heck reaction that was assisted by silver salt, and it revealed the significant role of P(O)Ar2for excellent yields and diastereoselectivity.

A Pd-catalyzed enantioselective C–H carbonylation by desymmetrization was developed with commercially available L-pyroglutamic acid as chiral ligand. Isoquinolinones were successfully obtained with good yields and high enantioselectivities. Mechanistic studies and DFT calculations provided a reasonable reaction pathway.

The Pd/Cu cocatalyzed oxidative tandem C–H aminocarbonylation and dehydrogenation was developed, affording carbolinones with molecular oxygen as the terminal oxidant. Natural product strychnocarpine and its derivatives were prepared conveniently using this strategy.

Oxidative allylic C–H alkylation with 2-naphthols was accomplished with excellent chemoselectivities and broad substrate scope through Pd(PPh3)4/Cu(MeCN)4PF6cooperative catalysis under mild base-free conditions. Special tolerance was observed with peptides, allowing late-stage modifications of peptides. The transformation provides a general protocol to obtain functionalized cyclohexadienones with quaternary carbon centers under two alternative sets of conditions and serves as a complementary catalysis system for the dearomatization of 2-naphthols.

Herein, we report the first atroposelective C(sp2)–H bond acyloxylation enabled by a phosphine oxide directing group. Uniquely, this transformation is shown to proceed through an eight-membered palladacycle intermediate, as opposed to the kinetically and thermodynamically favored five-membered palladacycle intermediate. Additionally, l-pGlu-OH, a cheap and abundant chiral amino acid derivative, was identified as the best chiral ligand to promote this atroposelective remote CH functionalization reaction.

Bismuth selenide (Bi2Se3), with a wide bulk band gap and single massless Dirac cone at the surface, is a promising three-dimensional topological insulator. Bi2Se3possesses gapless surface states and an insulator-like bulk band gap as a new type of quantum matter. Different Bi2Se3nanostructures were prepared using electron beam evaporation with high production efficiency. Structural investigations by energy-dispersive X-ray analysis, scanning electron microscopy, and X-ray diffraction revealed the sample stoichiometries and the structural transition mechanism from nanocrystals to nanoflakes. The optical properties systematically probed and analyzed by spectroscopic ellipsometry showed strong dependence on the nanostructures and were also predicted to have structure-modifiable technological prospects. The optical parameters, plasma frequencies, scattering rates of the free electrons, and optical band gaps were related to the topological properties of the Bi2Se3nanostructures via light–matter interactions, offering new opportunities and approaches for studies on topological insulators and spintronics. The high-quality Bi2Se3nanostructures provide advantages in exploring novel physics and exploiting prospective applications.

The coordination model of UAV network is attracting widespread attention. Considering from the flight characteristics of UAV, the Ad Hoc network should be adopted. This paper analyzes the characteristics of Ad Hoc network, and focuses on the further discussion on the physical layer technology OFDM to conclude that the application of OFDM technology in the UAV network communication can improve the data transmission capability.

Prosperous coupling: A nickel‐catalyzed CP cross‐coupling reaction with Me3SiPPh2by carbon–cyano bond cleavage has been developed. This method is characterized by its simplicity and wide application to the synthesis of various monophosphorus and P,N bidentate ligands (see scheme).

An acid for a phosphine: A versatile protocol for preparation of various di(phenyl)phosphoryl oxides was developed by copper‐catalyzed decarboxylative coupling of alkenyl, alkynyl carboxylic acids, and N‐benzylproline, respectively, with R2P(O)H (see scheme). All classes of products are important precursors for preparation of biologically active molecules and various phosphorus ligands. This finding represents the first example of copper‐catalyzed decarboxylative coupling to construct CP bonds.

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A new relay C–H functionalization of di([1,1′-biphenyl]-2-yl)phosphine oxide to obtain esterified and hydroxylated products with different hypervalent iodines as oxidants under palladium catalysis is disclosed. This reaction provides a more effective and concise strategy for the synthesis of novel structural hybrid-arylcyclophosphorus ligand precursors with a wide range of substrates and good functional group tolerance.

A novel method for P-involved heterocycle ring-closing–ring-opening rearrangement (HRR) via the Heck reaction is disclosed. The approach enables direct installation of a phosphorus-containing aryl group onto the C2 position of indole. This new rearrangement directly transforms easily prepared indole derivatives into indolyl-derived phosphonates and phosphinic acids with high yields, and many of the products are difficult to obtain by using established methods. This new HRR reaction provides an extremely simple and step-economic method to induce C–C bond formation and P–N bond cleavage for the synthesis of a variety of indolyl-type ligands.

A novel protocol for the synthesis of 3‐alkylideneoxindoles via Ag‐catalyzed aromatic C—H functionalization of diazoamides is given.

Under optimized conditions, a wide variety of aryl/heteroaryldiphenylphosphanes is prepared including potential P,N‐bidentate ligands using Me3SiPPh2 as phosphorus source.

A versatile protocol for preparation of various di(phenyl)phosphoryl oxides is developed by copper‐catalyzed decarboxylative coupling of alkenyl, alkynyl carboxylic acids, and N‐benzylproline, respectively, with R2P(O)H.

Slightly different conditions are necessary to produce a broad spectrum of the desired scaffolds.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

For Abstract see ChemInform Abstract in Full Text.