Boron antimony compounds

The chemistry of boron-phosphorus compouuds has been reviewed. Numerous boron-phosphorus derivatives have been reported, but relatively few boron-arsenic or boron-antimony compounds have been described. Boron-phosphorus compounds are similar in many ways to boron nitrogen derivatives, but the teudeucy to share boudiug electrons in covalent tetrahedral compounds is much more evident with phosphorus thau with uitrogeu. lu fact, most boron phosphorus chemistry iuvolves tetrahedral borou. They are typically either phosphiue-boraue complexes, such as R3P BR j, or phosphinoboranes (R2PBR2) , cyclic or polymeric derivatives of the hypothetical H3P BH3. The chemistry of these compounds and that of boron phosphate and thiophosphate is described below. Boron phosphides are discussed in Section 2.6. 

The most commonly used and widely marketed GC detector based on chemiluminescence is the FPD [82], This detector differs from other gas-phase chemiluminescence techniques described below in that it detects chemiluminescence occurring in a flame, rather than cold chemiluminescence. The high temperatures of the flame promote chemical reactions that form key reaction intermediates and may provide additional thermal excitation of the emitting species. Flame emissions may be used to selectively detect compounds containing sulfur, nitrogen, phosphorus, boron, antimony, and arsenic, and even halogens under special reaction conditions [83, 84], but commercial detectors normally are configured only for sulfur and phosphorus detection [85-87], In the FPD, the GC column extends... 

In the halide group the most active lone pair is found in the phosphortrihalides. The stability of the boron complexes AXZ.BXZ decreases in the sequence PXj -> AsXz SbX3, no antimony compounds being observed. The halides of the sulphur group do not form compounds at all it seems improbable that the only reason for this behaviour is the disproportionation of these halides. 

Enamels - [BARIUMCOMPOUNDS] (Vol3) - [ALUMINUMCOMPOUNDS - ALUMINIUMOXIDE(ALUMINA) - CALCINED,TABULAR, AND ALUMINATE CEMENTS] (Vol2) - [TIN COMPOUNDS] (Vol 24) -aluminum fluoride in [FLUORINE COMPOUNDS,INORGANIC - ALUMINUM](Vol 11) -antimony compds in [ANTIMONY COMPOUNDS] (Vol 3) -borate in [BORON COMPOUNDS - BORON OXIDES, BORIC ACID AND BORATES] (Vol 4) -boric oxide in prepn of [BORON COMPOUNDS - BORON OXIDES, BORIC ACID AND BORATES] (Vo 14) -lithium for [LITHIUM AND LITHIUM COMPOUNDS] (Vol 15)... 

Boron compounds Potassium dichromate Antimony compounds Bismuth compounds Periodates Litharge... 

The first cross-linking agents were borax and other boron compounds, antimony compounds e.g. ammonium pyroantimonate, potassium antimony tartrate followed by adding a dichiomate, that is oxidation of trivalent to penta-valent antimony was found to give an efficient cross-linking agent [74]. 

Similar treatment of ZSM-5 with boron, antimony, or magnesium compounds or silanes modifies catalyst performance in a comparable way. These improved yields of olefins obtained with deactivated ZSM-5 appear to be a result of changes in selectivity as well as the decrease in activity. Dilution of the methanol feed with steam or inert diluent also increases ethylene yieldfrom methanol over HZSM-5 catalysts at relatively low temperatures, below 600 K. Many of these patents also include examples using various other ZSM zeolites, but all the papers published so far deal with ZSM-5 only. 

Antimony compounds are synergistic with several other inorganic additives such as boron, molybdenum, and zinc compounds as well as with alumina trihydrate. 

In spite of the few thousands of references on flame retardants, only a small number of compounds are commercially produced as such. They are mainly phosphorus, antimony, aluminum, and boron-containing compounds, chlo-... 

The role of Lewis acids in the formation of oxazoles from diazocarbonyl compounds and nitriles has primarily been studied independently by two groups. Doyle et al. first reported the use of aluminium(III) chloride as a catalyst for the decomposition of diazoketones.<78TL2247> In a more detailed study, a range of Lewis acids was screened for catalytic activity, using diazoacetophenone la and acetonitrile as the test reaction.<80JOC3657> Of the catalysts employed, boron trifluoride etherate was found to be the catalyst of choice, due to the low yield of the 1-halogenated side-product 17 (X = Cl or F) compared to 2-methyI-5-phenyloxazole 18. Unfortunately, it was found that in the case of boron trifluoride etherate, the nitrile had to be used in a ten-fold excess, however the use of antimony(V) fluoride allowed the use of the nitrile in only a three fold excess (Table 1). 

Flame resistance A1203, antimony oxides, boron compounds, halogen compounds, phosphate esters, metal hydrates, magnesium compounds, tin compounds, molybdenum compounds, silicones Al, B, Br, Cl, Mo, P, Sb, Si, Sn, Zn... 

Antimony and other inorganic compounds (tin, molybdenum, aluminium, magnesium, iron, boron, with ATH accounting for about 40 % in volume of FR shipments in Europe). 

Various ways to modify ZSM-5 catalyst in order to induce para-selectivity have been described. They include an increase in crystal size (15,17,20) and treatment of the zeolite with a variety of modifying agents such as compounds of phosphorus (15,18), magnesium (15), boron (16), silicon (21), antimony (20), and with coke (14,18). Possible explanations of how these modifications may account for the observed selectivity changes have been presented (17) and a mathematical theory has been developed (22). A general description of the effect of diffusion on selectivity in simple parallel reactions has been given by Weisz (23). 

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. 

Reactions with reducing agents can be explosive. The compound attacks most metals almost as vigorously as fluorine. It spontaneously ignites boron, silicon, phosphorus, arsenic, antimony, and iodine at ordinary temperatures. 

The fuels are finely powdered metals (2.0-10.0 g) among which titanium, zirconium, manganese, tungsten, molybdenum and antimony are very common. Sometimes, non-metal powders such as boron and silicon (for fast burning delays), binary alloy powders such as ferrosilicon, zirconium-nickel, aluminum-palladium and metal compounds such as antimony sulfide, calcium silicide etc. are also used. 

Difluoro-l-silacyclobutane is obtained by the exchange of two chlorine atoms for fluorine in the 1,1-diehloro analog using antimony(III) fluoride in w-xylene yield 46% bp 36 -38 C.64 Antimony(lll) fluoride is supposed to interact, through its lone electron pair, with coordinative-ly unsaturated silicon rather than with chlorine atoms at silicon. Because of this Si —Cl compounds are fluorinated slower than C — Cl derivatives in the presence of boron trifluoride.65... 

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