Phosphorus and Arsenic

Bennett et also claim that the nitric acid oxidation of hydroxyl-amine gives dinitrogen in addition to the products described previously. This is attributed to the reaction between hyponitrous acid and nitrous acid, which seems unlikely. Nevertheless, this is an interesting observation, and clearly there is considerable scope for the use of labels in sorting out these problems of stoicheiometry and mechanism. 

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Nitrogen, phosphorus and arsenic form more than one hydride. Nitrogen forms several but of these only ammonia, NHj, hydrazine, N2H4 and hydrogen azide N3H (and the ammonia derivative hydroxylamine) will be considered. Phosphorus and arsenic form the hydrides diphosphane P2H4 and diarsane AS2H4 respectively, but both of these hydrides are very unstable. 

USING OF THE MICELLAR MEDIUM, BASIC DYES AND PRECONCENTRATION ON THE POLYURETHANE FOAMS FOR THE DETERMINATION OF PHOSPHORUS AND ARSENIC... 

Antimony is a bluish white metal with good lustre but poor heat conducting ability. It is stable in air and resistant to dilute acids but attacked by halogens, sulphur, phosphorus and arsenic. 

Besides the thiocyanates, just mentioned, other 5-donor complexes which are of interest are the dialkyl sulfides, [MCl3(SR2)3], produced by the action of SR2 on ethanolic RhCl3 or on [IrClg] ". Phosphorus and arsenic compounds are obtained in similar fashion, and the best known are the yellow to orange complexes, [ML3X3], (M = Rh, Ir X = Cl, Br, I L = trialkyl or triaryl phosphine or arsine). These compounds may exist as either mer or fac isomers, and these are normally distinguished by their proton nmr spectra (a distinction previously made by the measurement of dipole moments). An especially... 

E. Reactions with Sulfui , Selenium, Tellurium, Phosphorus, and Arsenic Derivatives.. . 171... 

E. Reactions with Sulfur, Selenium, tellurium. Phosphorus, AND Arsenic Derivatives... 

Complexes of tetradentate ligands containing phosphorus and arsenic. L. M. Venanzi, Angew. Chem., Int. Ed. Engl., 1964,3, 453-460 (27). 

Trihalides of Phosphorus and Arsenic.— Radial distribution curves for PF3, AsF3, PC13 and AsC13, calculated with the data given in Table VIII, are shown in Fig. 6. Each curve shows two... 

Fig. 6.—Radial distribution, curves for triflourides and trichlorides of phosphorus and arsenic.

Phosphorus and arsenic have nearly identical electronegativities, so in GaP Asi. , the dominant effect is the smaller atomic radius of P relative to As. Substituting P atoms for As atoms shrinks the dimensions of the semiconductor lattice. This leads to greater overlap of the valence orbitals, increased stability of the bonding orbitals (valence band), and an increased band gap. 

Silicon s atomic structure makes it an extremely important semiconductor. Highly purified silicon, doped with such elements as boron, phosphorus, and arsenic, is the basic material used in computer chips, transistors, sUicon diodes, and various other electronic circuits and electrical-current switching devices. Silicon of lesser purity is used in metallurgy as a reducing agent and as an alloying element in steel, brass, and bronze. 

Cyclovoltammetric measurements were performed for the derivatives 15a and 15d. Interestingly, a reversible one-electron reduction was observed (—80°C, DME, Bu4NPF5) at E = - 1.81 (15a) and -1.74 V (15d).14 In contrast, the analogous arsasilenes (Si=As) undergo only irreversible reduction. Compounds 15a,d show a further one-electron reduction, which is irreversible. This remarkably different reduction behavior of Si=P and Si=As bonds is probably caused by the small, but significant difference in the electronegativities of phosphorus and arsenic. 

C. Helling, V. Imhof, L. Nielsen, and E. Jacobson Complex Alumino-Hydrides containing Nitrogen, Phosphorus and Arsenic. Inorg. Chem. 2, 504 (1963). 

The preparation of similar precursors suitable for the deposition of metal nitrides is analogous to the preparations of phosphorus and arsenic compounds. The initial reaction of metal trialkyls MR3 (M = A1, Ga, In) with amines (NHR 2) results in the formation of oligomeric amido compounds [R2MNR 2] (n = 2 or 3) which eliminate alkanes on thermolysis. The incorporation of a proton as a substituent on the pnictide bridging ligand has been examined, and many compounds of the type [R2MNHR ]2 have been synthesized. The presence of this proton may facilitate /3-elimination, allowing lower deposition temperatures to be used. 

Tris(a-hydroxy-/3,/3,/3-trichloroethyl)phosphine reacts with phenyl-trichlorosilane, phosphorus, and arsenic trichlorides in the same way, giving bicyclic product (14) [Eq. (12)] (78ZOB2437). 

Numerous reactions of carbonyl compounds, alcohols, olefins, etc., with compounds bearing E14=X bonds in which the latter act as direct analogs of phosphorus and arsenic ylides have already been accomplished.17 Recently, an interest in reactivity of compounds with multiple E14-X bonds is increasing due to challenges of important practical applications (see,... 

Reactions of Phosphorus and Arsenic Ylides with Organocyclosilthianes and... 

As mentioned above (see Scheme 1), three main directions of the decomposition of intermediates that formed are possible when phosphorus and arsenic ylides react with compounds bearing C=X bonds 5,6,19,63,64,88 (i) elimination of R3E15=X to form olefins (Wittig type reaction) (ii) retro-Wittig type decomposition and (iii) elimination of R3E15 and formation of three-membered cycles (Corey-Chaykovsky type reaction). According to the data of Erker and coworkers,12,13,51 under kinetic control, the reaction of phosphorus ylides with thiocarbonyl compounds also affords phosphines and thiiranes, whose further transformations lead to olefins and R3PS under thermodynamic control. 

Isomerization of Betaines to Metallated Phosphorus and Arsenic Ylides (Direction A)... 

The thermodynamic data presented in Table XYI are calculated for the temperature T=0K. Note that the entropy factor favors betaine decomposition via directions A and B at higher temperatures. The reactions of organoelement analogs of carbenes with phosphorus and arsenic ylides are yet poorly studied. The presented above results of calculations allow an optimistic prognosis about the possibility of developing a new method for the synthesis of elementaolefins R2E14=CH2 (E14 = Si, Ge, Sn) on the basis of these reactions. 

In summary, the solubility and the degree of aggregation of dimeta-lated phosphanes and arsanes can be controlled by employing appropriate lipophilic substituents at phosphorus and arsenic. Triorganosi-lyl substituents fulfill this requirement especially well. The tendency... 

This technique has been applied to the determination of boron, total phosphorus and arsenic in soil, antimony and organosilicon compounds in non-saline sediments, arsenic in saline sediments and silicon and arsenic in sludges. 

Synthesis and Structural Principles of Main Croup Metal-Nitrogen, Phosphorus and Arsenic Rich Clusters... 

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