Phosphorus, arsenic, antimony and bismuth

Phosphorus, Arsenic, Antimony, and Bismuth.— The crystal and molecular structure of tetrakis(pentafluorophenyl)cyclotetraphosphane has been determined. The P4 ring is non-planar, and has a two-fold symmetry axis, with a P— P bond length of 223.6 pm and an average P—C bond length of 183.8 pm.  

Utvary, Allg.prakt. Chem., 1971, 22, 301 (Chem. Abs., 1972, 76, 52568e). 

spectroscopic study of substituent effects in triphenyl-arsines and -stilbenes has included the compound (C F5)jSb. Tris(pentafluorophenyl)-bismuth has been prepared by the Grignard route. It undergoes hydrolysis to pentahuorobenzene, and thermal transmetallation reactions with the elements mercury, iridium, tin, arsenic, and sulphur, yielding (C,F,)aHg (57%), (C,Fg)aIn (15 a (C.F )4Sn (48%), (C.Fg),As (73%), and (C,Fg)aS (47%), respectively.  

Sulphur and Sdeniiun.— The vibrational spectra of pentafluorobenzenethiol have been measured and assigned.  

A novel electrophilic route to bis(pentafluorophenyI) sulphide involves the reaction of pentafluorobenzene with sulphur, sulphur mono- or dichloride, or pentafluorobenzenesulphenyl chloride in the presence of antimony pentafiuoride. Photochemical reaction of pentafluoroiodobenzene with bis(trifluoromethyl) disulphide yields a mixture of the sulphide CgFg-S-CFj, disulphide CeFg-S-S CFs, and trifluoroiodomethane. Thiourea is suffident- 

As mentioned earlier, there are many nitrogen compounds that are either explosives or propellants. That is one reason why nitrates and nitric acid have been so important throughout several centuries of history. 

All of the elements are important, and they are found in many common compounds. Some phosphorus compounds are among the most useful and essential of any element. As a result, there is a great deal more extensive chemistry of phosphorus, and more space will be devoted to it in this chapter. Much of the chemistry of the other elements can be inferred by comparison to the analogous phosphorus compounds but realizing the greater metallic character of As and Sb. 

Phosphorus compounds occur widely in nature, with some of the most common forms being phosphate rocks and minerals, bones, and teeth. Phosphate minerals include calcium phosphate, Ca3(P04)2 apatite, Ca5(P04)30H fluoroapatite, Ca5(P04)3F and chloroapatite, Ca5(P04)3Cl. Elemental phosphorus was first obtained by H. Brand, and its name is derived from two Greek words meaning light and I bear because of the phosphorescence of white phosphorus due to slow oxidation. 

Phosphorus is prepared on an industrial scale by reduction of naturally occurring phosphates. Crushed phosphate rock, carbon, and silica (Si02) are heated to 1200 to 1400 °C in an electric furnace from which phosphorus is removed by distillation. 

Several allotropic forms of phosphorus are known, the most common of which are the white, red, and black forms. Heating the white form at 400 °C for several hours produces red phosphorus, which is known to include several forms. A red form that is amorphous can be prepared by subjecting white phosphorus to ultraviolet radiation. In the thermal process, several substances (I2, S8, and Na) are known to catalyze the conversion of phosphorus to other forms. Black phosphorus consists of four identifiable forms that result when white phosphorus is subjected to heat and pressure. Phosphorus is used in large quantities in the production of phosphoric acid and other chemicals. White phosphorus has been used extensively in making incendiary devices, and red phosphorus is used in making matches. 

The members of group of the periodic table show the expected trend in properties with increasing atomic number (f able 21 1) nitrogen is a gas which can be condensed to a liquid only at very low temperatures phosphorus (in the modification called w I tilt phosphorus) is a low-melting non-metal and arsenic, antimony, and bismuth are metalloids with increasing metallic character. 

The similarity of the elements is indicated by the formulas of their hydrides, NH3 (ammonia), PH (f osphine), AsHg (arsine), SI3H3, and BiHg, and of their highest oxides, NgO, P2O-, As O, Sb O., and Bi20-. This similarity is far from complete, however the principal acids formed by nitrogen, phosphorus, arsenic, and antimony have different formulas  

Nitric acid Phosphoric acid Arsenic acid Antimonic acid 444 

The most striking deviation from regularity in properties of these elements is the smaller stability and greater reactivity of tlie heavier elements than of elementary nitrogen. -Whereas nitrogen can be made 

Phosphorus, like nitrogen and the other members of the fifth group, has oxidation states ranging from —3 to +5. The principal compounds of phosphorus are indicated in the following chart  

---

F. G. Mann, The Heterocyclic Derivatives of Phosphorus, Arsenic, Antimony and Bismuth, 2nd ed., Wiley-Interscience, New York, 1970. 

Phosphorus, arsenic, antimony and bismuth multiply bonded systems with low coordination number — their role as complex ligands. O. J. Scherer, Angew. Chem., Int. Ed. Engl., 1984, 24, 924 (85). 

Phosphorus, Arsenic, Antimony and Bismuth Ligands Oxygen Ligands... 

Many of the properties of the group 15 element diheteroferrocences are very similar to ferrocenes and other metallocenes. It seems justified to regard the diheteroferrocenes as perturbed ferrocenes just as we regard the group 15 heterobenzenes as perturbed benzenes. Thus, it is very clear that the elements phosphorus, arsenic, antimony, and bismuth can take part in 7r-bonding in a manner similar to carbon. 

CHEC-II(1996) comprehensively outlines the most commonly used synthetic approaches applied to these types of bicyclic compounds of phosphorus, arsenic, antimony, and bismuth <1996CHEC-II(8)863>. The six classes of compounds listed in this section have received considerable attention over the review period and as such the principal synthetic methods for these compounds are discussed. Schoth et al. <2000CCR101> have reviewed the use of fluorinated 1,3-diketones, 2-trifluoroacetylphenols, and their derivatives in the synthesis of phosphorus compounds. Included in this review is the use of these reagents for the synthesis of various [3.3.1] nonfused and [3.3.0] fused phosphorus bridgehead bicyclic systems. 

Bodner, G.M., Gagnon, C., and Whittern, D.N., A Fourier transform carbon-13 NMR study of trivalent compounds of phosphorus, arsenic, antimony and bismuth, and their LNi(CO)3 complexes, J. Organomet. Chem., 243, 305, 1983. 

PHOSPHORUS, ARSENIC, ANTIMONY AND BISMUTH 3.13.1 Tributyl phosphate149... 

Hemnaun, W A. and H.H. Karech Synthetic Methods of Orgunomeuilbc and Inorganic Chemistry, Phosphorus, Arsenic, Antimony, and Bismuth, Vol W, Thie me Medical Publishers, Inc., New York. NY, 1996. 

Because of factors beyond the editors control, the submission of the manuscript for this chapter was delayed. In order to minimize any delay in publishing Comprehensive Coordination Chemistry as a whole, the coverage of phosphorus, arsenic, antimony and bismuth ligands appears at the end of this volume, commencing on page 989. 

---