DIAMAGNETIC SUSCEPTIBILITIES OF SOME COMPOUNDS CONTAINING OXYGEN LINKED TO NITROGEN OR PHOSPHORUS

1964 ◽  
Vol 42 (8) ◽  
pp. 1817-1821 ◽  
Author(s):  
M. W. Lister ◽  
R. Marson
Keyword(s):  
Amine Oxide ◽  
Phosphine Oxides ◽  
Trialkyl Phosphates ◽  
Trialkyl Phosphites ◽  
Dialkyl Phosphites ◽  
Carboxylic Esters ◽  
Usual Formula ◽  
Extra Oxygen ◽  
Oxygen Atoms

The diamagnetic susceptibilities of a number of compounds containing oxygen linked to nitrogen or phosphorus have been measured. The results are interpreted in terms of the apparent contribution of the oxygen atoms to the susceptibility in these and other series of compounds, and are compared with other evidence on the nature of the bonds to oxygen. The results support the usual formula of an amine oxide as R3N → O, but phosphine oxides behave as would be expected for R3P = O. Phosphorus oxyhalides have molar susceptibilities about 4.6 (in units of −10−6 e.m.u.) larger than the corresponding trihalides, a difference close to that for singly bound oxygen in ethers or alcohols. Each oxygen contributes 4.4 in trialkyl phosphites, as might be expected for P(OR)3; but the value in dialkyl phosphites is 4.9 per oxygen, thereby showing behavior similar to that of carboxylic esters. The extra oxygen in trialkyl phosphates as compared with trialkyl phosphites contributes 9.4, a surprisingly large amount.

Friedel-Crafts Alkylation of Aromatic Compounds with Phosphorus Esters

1972 ◽  
Vol 27 (11) ◽  
pp. 1339-1348 ◽  
Author(s):  
G. Sosnovsky ◽  
M. W. Shende
Keyword(s):  
Aluminum Chloride ◽  
Aromatic Compounds ◽  
Heterogeneous Reaction ◽  
Isomer Distribution ◽  
Aromatic Substrates ◽  
Trialkyl Phosphates ◽  
Strong Lewis Acid ◽  
Trialkyl Phosphites ◽  
Dialkyl Phosphites ◽  
Heterogeneous Reaction Conditions

The alkylations of aromatic compounds with trialkyl phosphites (1), dialkyl phosphites (2), and trialkyl phosphates (3) in the presence of aluminum chloride were studied involving several raction variables, such as time, ratio of reactants, nature of catalyst and solvent, and combinations thereof. Extensive disproportionation and isomerization were observed in the reaction with monosubstituted alkylbenzenes under heterogeneous reaction conditions obtained by the use of an excess of aromatic substrates. A combination of aluminum chloride—nitromethane complex and dichloromethane as solvent was used to eliminate these undesirable effects and to give homogeneous and practically non-isomerizing conditions. The scope of the reaction was studied with a number of aromatic substrates, and their relative reactivities were compared to that of benzene in competitive isopropylations with triisopropyl phosphite. The relative rates and isomer distributions showed low substrate and low positional selectivities and poor agreement with Brown’s selectivity relationship. The substrate selectivity was somewhat higher and the positional selectivities were somewhat lower than those obtained in competitive isopropylation reactions with other isopropylating agents. The selectivity factor, Sf, and partial rate factors were calculated. An electrophilic alkylation mechanism is proposed on the basis of (1) the relative rates of isopropylation, (2) the isomer distribution of dialkylated aromatics, and (3) the necessity of a strong Lewis acid in these reactions.

17O and 13C NMR spectra of some geminal diacetates

1988 ◽  
Vol 53 (3) ◽  
pp. 588-592 ◽  
Author(s):  
Antonín Lyčka ◽  
Josef Jirman ◽  
Jaroslav Holeček
Keyword(s):  
13C Nmr ◽  
Nmr Spectra ◽  
Chemical Shifts ◽  
The Other ◽  
13C Nmr Spectra ◽  
Other Hand ◽  
Carboxylic Esters ◽  
C Nmr ◽  
Oxygen Atoms

The 17O and 13C NMR spectra of eight geminal diacetates RCH(O(CO)CH3)2 derived from simple aldehydes have been measured. In contrast to the dicarboxylates R1R2E(O(CO)R3)2, where E = Si, Ge, or Sn, whose 17O NMR spectra only contain a single signal, and, on the other hand, in accordance with organic carboxylic esters, the 17O NMR spectra of the compound group studied always exhibit two well-resolved signals with the chemical shifts δ(17O) in the regions of 183-219 ppm and 369-381 ppm for the oxygen atoms in the groups C-O and C=O, respectively.

scholarly journals Organophosphorus Chemistry, 18

1990 ◽  
Vol 45 (7) ◽  
pp. 1027-1031 ◽  
Author(s):  
W. M. Abdou ◽  
H. A. Abd El Monem ◽  
M. R. Mahran
Keyword(s):  
New Products ◽  
The Other ◽  
Spectroscopic Measurements ◽  
Other Hand ◽  
Trialkyl Phosphites ◽  
Dialkyl Phosphites ◽  
Organophosphorus Chemistry

Trialkyl phosphites (2a—c) react with 1,8-naphthosultam (6) to give the respective N-alkylated products 7 a—c. Compounds 7a—c were also prepared by the action of dialkyl phosphites on 6 in the presence of p-TsOH. Moreover, 7 a could be obtained by treating 6 with DMMP (8). On the other hand, chlorinated phosphorus reagents (11) condense with 6 to give products of type 12. Structures of the new products were assigned according to consistent analytical and spectroscopic measurements.

ChemInform Abstract: P-Arylation of Dialkyl Phosphites and Secondary Phosphine Oxides with Arynes.

ChemInform ◽  
2016 ◽  
Vol 47 (20) ◽  
Author(s):  
Qian Chen ◽  
Xinxing Yan ◽  
Zhiyun Du ◽  
Kun Zhang ◽  
Chunxiao Wen
Keyword(s):  
Secondary Phosphine ◽  
Phosphine Oxides ◽  
Dialkyl Phosphites

On the Origin of the Structural Modulation in the Bi Cuprates As Derived from 3d-Metal Substituted Phases

1989 ◽  
Vol 156 ◽  
Author(s):  
J. M. Tarascon ◽  
Y. LePage ◽  
W. R. McKinnon ◽  
E. Tselepis ◽  
P. Barboux ◽  
...  
Keyword(s):  
Single Crystal ◽  
X Ray ◽  
Structural Modulation ◽  
Doping Mechanism ◽  
Perovskite Type ◽  
Extra Oxygen ◽  
Oxygen Atoms

ABSTRACTA substitution for Cu by a 3d-metal (Fe, Co, Mn) in the superconducting Bi phases (Bi2Sr2Can−1CunOy; n = 1,2 and 3) has led to the discovery of new phases. These 3d-metal substituted phases are non-superconducting and, in contrast to the Cu-based phases, they exhibit a structural modulation that is commensurate. Single crystal x-ray studies were performed on the Bi2Sr3Fe2Oy, Bi2Sr2CoOy and Bi2Sr2MnOy compounds. A result, in common, is that the modulation is caused by the periodic insertion of a row of oxygen atoms in the Bi layers and this results in a corrugated-like slab structure. The Bi-O layers can be described as composed of alternating rocksalt-type and oxygen deficient perovskite-type blocks. For the Fe (n=2) phase the Bi atoms form ribbons (chains) in the ab plane. This is in contrast to the n=1 Co or Mn phases for which a disorder at the oxygen position is observed. Although the extra oxygen in the Bi-O layer could account for the doping mechanism in the high Tc Bi-phases, cation non-stoichiometry may also beimportant.

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