Novel single or double insertion of alkynes into rhodium– and iridium–oxygen or –phosphorus atom bonds and transannular addition of 1-alkynes between the rhodium atom and the ipso-carbon atom of the phosphorus ligand

2001 ◽  
pp. 195-211 ◽  
Author(s):  
Yasuhiro Yamamoto ◽  
Kenichiro Sugawara ◽  
Xiao-Hong Han
Keyword(s):  
Carbon Atom ◽  
Phosphorus Atom ◽  
Rhodium Atom

scholarly journals A soft phosphorus atom to “harden” an erbium(iii) single-ion magnet

2018 ◽  
Vol 9 (38) ◽  
pp. 7540-7545 ◽  
Author(s):  
Shi-Ming Chen ◽  
Jin Xiong ◽  
Yi-Quan Zhang ◽  
Qiong Yuan ◽  
Bing-Wu Wang ◽  
...  
Keyword(s):  
Carbon Atom ◽  
Phosphorus Atom ◽  
Blocking Temperature

A single-ion magnet (Dsp)Er(COT) was obtained by replacing a carbon atom of [Cp*]− in (Cp*)Er(COT) by a soft P atom. Both relaxation barrier and blocking temperature are improved.

scholarly journals [(1,2,5,6-η)-Cycloocta-1,5-diene](1-ethyl-3-isopropyl-1,3-imidazol-2-ylidene)(triphenylphosphane)rhodium(I) tetrafluoridoborate

IUCrData ◽  
2021 ◽  
Vol 6 (6) ◽  
Author(s):  
Jeffrey A. Rood ◽  
Chhatra B. Subedi ◽  
John P. Risell ◽  
Andrei V. Astashkin ◽  
Edward Rajaseelan
Keyword(s):  
Carbon Atom ◽  
Phosphorus Atom ◽  
Counter Anion ◽  
Cationic Complex ◽  
Coordination Sites ◽  
Square Planar ◽  
Planar Environment

A new N-heterocyclic cationic rhodium(I) complex with a tetrafluoridoborate counter-anion, [Rh(C8H14N2)(C8H12)(C18H15P)]BF4, has been prepared and structurally characterized. The cationic complex exhibits a distorted square-planar environment around the rhodium(I) ion. Two connections are made from rhodium(I) to the carbon atom of an N-heterocylic carbene ligand and to the phosphorus atom of a triphenylphosphane ligand. The remaining two coordination sites are made via a bidentate interaction from the two olefinic bonds of cyclooctadiene to the rhodium(I) ion. The compound includes an out-sphere tetrafluoridoborate counter-anion. Within the crystal of the compound exist several weak intermolecular C—H...F interactions.

Trinuclear Mixed-valent Gold Complexes Derived from 2-C6F4PPh2: Phosphine Oxide Complexes of Gold(III) and an ortho-Metallated Complex of Gold(I)

2009 ◽  
Vol 64 (11-12) ◽  
pp. 1463-1468 ◽  
Author(s):  
Martin A. Bennett ◽  
Nedaossadat Mirzadeh ◽  
Steven H. Privér ◽  
Jörg Wagler ◽  
Suresh K. Bhargava
Keyword(s):  
Carbon Atom ◽  
Silver Nitrate ◽  
Phosphine Oxide ◽  
Phosphorus Atom ◽  
Phenyl Group ◽  
Large Excess ◽  
Gold Complexes ◽  
Nitrate Ion ◽  
Metal Atoms

Crystals of two mixed-valent gold complexes [(O2NO)AuI(μ-2-C6F4PPh2)AuIII{κ2-2-C6- F4P(O)Ph2}(μ-2-C6F4PPh2)AuI(ONO2)] (14) and [(O2NO)AuI(μ-2-C6F4PPh2)AuIII{κ3-2-C6F4- P(O)Ph(C6H4)}(μ-2-C6F4PPh2)AuI] (15) have been obtained from the reaction of the digold(I,III) complex [ClAuI(μ-2-C6F4PPh2)(κ2-2-C6F4PPh2)AuIIICl] (5) with, respectively, a small and a large excess of silver nitrate. Both complexes contain three, approximately collinear metal atoms, the central gold(III) atom being planar-coordinated by a chelate (O,C)-phosphine oxide formed by oxidation of 2-C6F4PPh2 and the carbon atoms of two bridging 2-C6F4PPh2 groups. In 14 each of the terminal gold(I) atoms is coordinated by a monodentate nitrate ion and the phosphorus atom of μ-2-C6F4PPh2, whereas in 15 the nitrate ion on one of the gold(I) atoms of 14 has been replaced by the carbon atom of a bridging C6H4 group derived by Ag+-promoted cyclometallation of a phenyl group on the neighbouring phosphine oxide

2-YIidvl-1,3,2-oxathiaphosphole und -oxaselenaphosphole / 2-Ylidyl-1,3,2-oxathiaphospholes and -oxaselenaphospholes

1995 ◽  
Vol 50 (10) ◽  
pp. 1543-1549 ◽  
Author(s):  
Alfred Schmidpeter ◽  
Stefan Plank ◽  
Kurt Polborn
Keyword(s):  
Molecular Structure ◽  
Carbon Atom ◽  
Strong Interaction ◽  
Phosphorus Atom ◽  
Type Reaction

Ylidyl thioxophosphines or selenoxophosphines and phenacyl halides undergo addition in a 1:1 ratio and yield in the presence of triethylamine the title compounds. The molecular structure of an ylidyl oxathiaphosphole demonstrates a strong interaction between the ylid substituent and the heterocycle, making the exocyclic PC-bond unusually short and the endocyclic PO- and PS-bonds considerably longer than normal for a pyramidal phosphorus atom.The ylidyl chalcogenoxophosphines are oxidized by sulfur or selenium at the phosphorus atom and protonated at the ylidic carbon atom. No Wittig-type reaction is observed.

A simple method of calculating the molecular rotations of the sulfur, nitrogen and phosphorus analogues of α-D-glycopyranoses having different substituents at the anomeric carbon atom

1984 ◽  
Vol 37 (5) ◽  
pp. 971 ◽  
Author(s):  
B Poh
Keyword(s):  
Carbon Atom ◽  
Phosphorus Atom ◽  
Nitrogen And Phosphorus ◽  
Simple Method ◽  
Anomeric Carbon ◽  
Molecular Rotations ◽  
Anomeric Carbon Atom

The values of m and I of equation (1) for several series of α-D-glycopyranoses having different substituents at the anomeric carbon atom have been obtained earlier. From these values, the molecular rotations of the corresponding sugars containing a sulfur, nitrogen, or phosphorus atom in the ring have been calculated and found to agree satisfactorily with the corresponding literature values.

scholarly journals Primary Phosphines and Phosphine Oxides with a Stereogenic Carbon Center Adjacent to the Phosphorus Atom: Synthesis and Anti-Markovnikov Radical Addition to Alkenes

Organics ◽  
2021 ◽  
Vol 2 (4) ◽  
pp. 395-403
Author(s):  
Toshiaki Murai ◽  
Ryota Wada ◽  
Kouji Iwata ◽  
Yuuki Maekawa ◽  
Kazuma Kuwabara ◽  
...  
Keyword(s):  
Carbon Atom ◽  
Phosphorus Atom ◽  
Organophosphorus Compounds ◽  
Radical Addition ◽  
Secondary Phosphine ◽  
Phosphine Oxides ◽  
Reaction Conditions ◽  
High Yields ◽  
Oxidized Products

Organophosphorus compounds with stereogenic phosphorus and carbon atoms have received increasing attention. In this regards, primary phosphines with a stereogenic carbon atom adjacent to the phosphorus atom were synthesized by the reduction in phosphonates and phosphonoselenoates with a binaphthyl group. Their oxidized products, i.e., phosphine oxides with a stereogenic tetrasubstituted carbon atom, were found to undergo BEt3-mediated radical addition to cyclohexene to give P-stereogenic secondary phosphine oxides with a diastereoselectivity of 91:9. The products were characterized by ordinary analytical methods, such as Fourier transform infrared spectroscopy; 1H, 13C, and 31P NMR spectroscopies; and mass spectroscopy. Computational studies on the phosphorus-centered radical species and the obtained product implied that the thermodynamically stable radical and the adduct may be formed as a major diastereomer. The radical addition to a range of alkenes took place in an anti-Markovnikov fashion to give P-stereogenic secondary phosphine oxides. A variety of functional groups in the alkenes were tolerated under the reaction conditions to afford secondary phosphine oxides in moderate yields. Primary phosphines with an alkenyl group, which were generated in situ, underwent intramolecular cyclization to give five- and six-membered cyclic phosphines in high yields after protection by BH3.

An atomic resolution study of a carbide phase in platinum

1992 ◽  
Vol 50 (1) ◽  
pp. 20-21
Author(s):  
M.J. Witcomb ◽  
M.A. O'Keefe ◽  
CJ. Echer ◽  
C. Nelson ◽  
J.H. Turner ◽  
...  
Keyword(s):  
Solid Solution ◽  
Carbon Atom ◽  
Carbide Phase ◽  
Structural Changes ◽  
Critical Role ◽  
Alloy System ◽  
Atomic Resolution ◽  
Excess Carbon ◽  
Interstitial Carbon ◽  
Resolution Study

Under normal circumstances, Pt dissolves only a very small amount of interstitial carbon in solid solution. Even so, an appropriate quench/age treatment leads to the formation of stable Pt2C {100} plate precipitates. Excess (quenched-in) vacancies play a critical role in the process by accommodating the volume and structural changes that accompany the transformation. This alloy system exhibits other interesting properties. Due to a large vacancy/carbon atom binding energy, Pt can absorb excess carbon at high temperatures in a carburizing atmosphere. In regions rich in carbon and vacancies, another carbide phase, Pt7C which undergoes an order-disorder reaction was formed. The present study of Pt carburized at 1160°C and aged at 515°C shows that other carbides in the PtxC series can be produced.

Six-Membered Hetarenes with One Nitrogen or Phosphorus Atom

2005 ◽  
Author(s):  
D. StC. Black ◽  
D. Spitzner ◽  
P. A. Keller ◽  
R. D. Larsen ◽  
D. Cai ◽  
...  
Keyword(s):  
Phosphorus Atom

Potential Electron Scattering by Phosphorus Atom

2014 ◽  
Vol 59 (6) ◽  
pp. 569-580 ◽  
Author(s):  
V.I. Kelemen ◽  
◽  
M.M. Dovhanych ◽  
E.Yu. Remeta ◽  
◽  
...  
Keyword(s):  
Electron Scattering ◽  
Phosphorus Atom

Mass spectra of 4,4-dimethyl-A-homo-4a,6-cholestadien-3-ols, 4,4-dimethyl-A-homo-5-cholestene-3,4a-diols and their derivatives

1982 ◽  
Vol 47 (10) ◽  
pp. 2768-2778
Author(s):  
Antonín Trka ◽  
Helena Velgová
Keyword(s):  
Carbon Atom ◽  
Electron Impact ◽  
Mass Spectra ◽  
Molecular Ions

Partial electron impact induced mass spectra are given of 3α-hydroxy-, 3β-hydroxy-, 3β-methoxy-, 3α-acetoxy- and 3β-acetoxy-4,4-dimethyl-A-homo-4a,6-cholestadienes, 3α,5α-epoxy-4,4-dimethyl-A-homo-5-cholestane, isomeric 4,4-dimethyl-A-homo-5-cholestene-3α(β),4aα(β)-diols, their 3-acetoxy derivatives and 3-methyl ethers. The fragmentation of the molecular ions of these substances involves the usual elimination of substituents (in the form of H2O, CH3OH, CH3COOH, CH2CO), but the most abundant and characteristic ions are products of the contraction of ring A (to a six- or five-membered one), accompanied by expulsion of a fragment containing the carbon atom C(4) with both methyls.

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