Acetylenic phosphorus compounds

Chlorine Ammonia, acetylene, alcohols, alkanes, benzene, butadiene, carbon disulflde, dibutyl phthalate, ethers, fluorine, glycerol, hydrocarbons, hydrogen, sodium carbide, flnely divided metals, metal acetylides and carbides, nitrogen compounds, nonmetals, nonmetal hydrides, phosphorus compounds, polychlorobi-phenyl, silicones, steel, sulfldes, synthetic rubber, turpentine... 

Remarkable enhancements of the unimolecular c-t isomerization of c-S with p-MeO and oxidation of S with -MeO are explained by charge-spin separation in such S Unimolecular c-t isomerization of such c-S proceeds with a chain mechanism, while regioselective oxidation occurs in such S because of the spin localization. Cycloreversion of t,c,t-TPCB occurs to give a a-St 2, while the photochemical cycloreversion of TPCB and t,t,t-TPCB gives Tr-St 2 and t-St /t-St pair, respectively. Radical cations of phosphorus compounds (9 and 10 form intramolecular rr-dimer between two Nps from which Np 2 forms. Formation of intermolecular a-dimer of aromatic acetylene (11 - and 12 -) and intramolecular dimer of 13 and diarylmethanoT was observed, and the n = 3 rule is not effective for intramolecular dimer -. 

We have shown without any doubt the formation of carbanions obtained when trivalent phosphorus compounds react with an acetylenic compound. Trapping of these carbanionic species with protic reagents, alcohol for instance,leads to an ylid A. An alternative pathway involves reaction on the phosphorus atom leading to a phosphorane JB. 

M. A. Shaw u.R.S. Ward, Addition Reactions at tertiary Phosphorus Compounds with Electrophilic Olefins and Acetylenes, Topics in Phosphorus Chemistry 7, 1 (1972). 

Besides processes (1) and (2), the reader should be aware that nucleophilic attacks on alkynes are treated in other chapters of this book, dealing with rearrangements, cyclizations, polyacetylenes, cyclic acetylenes and perhaps others. A number of publications overlap with ours in different ways and at different levels -. They treat individual alkynes or families " , e.g. acetylene, diacetylenes , acetylene dicarboxylic esters haloacetylenes , alkynyl ethers and thioethers > ynamines , fluoro-alkynes ethynyl ketpnes , nitroalkynes , etc. synthetic targets, e.g. pyrazoles , if-l,2,3-triazoles , isothiazoles , indolizines S etc. reagents, e.g. nitrones , lithium aluminium hydride , heterocyclic A -oxides - , azomethine ylids - , tertiary phosphorus compounds , miscellaneous dipolar nucleophiles - , etc. The reader will appreciate that all of these constitute alternate entries into our subject. 

Further reports have appeared on the reaction of trivalent phosphorus compounds with acetylene dicarboxylates. In the first, alkyl diphenylphosphinites (e.g.57) are shown to react with dialkylacetylene dicarboxylates (e.g.58) in the presence of carbon dioxide to form 1,2-oxaphosphol-3-enes (e.g.59) which in the presence of excess phosphinite decompose via (60) to give di-ylids (e.g.61). On the other hand, the phosphoranes (62) from phosphonites and phosphites react with a further phosphorus component to give the ylids (63) which are readily converted by treatment with alcohol into phosphonates (65) apparently via ketene intermediates (64) as evidenced by and isotopic tracer studies. ... 

There have been a number of developments worthy of special mention in chemistry involving pentaco-ordinated compounds and intermediates. These include reports of molecular mechanics calculations to study the hydrolysis of cyclic phosphorus esters, further detailed studies of the reactions of tervalent phosphorus compounds with acetylene carboxylates and the first synthesis of a pentaco-ordinated phosphorus compound containing a three-membered (phosphirene) ring. There has also been further elegant work in the area of phosphatrane chemistry. 

Maier, L., Organic phosphorus compounds. Part 58. Preparation and properties of acetylene diphos-phonates, haloethene-l,2-diphosphonates, and the corresponding acids. Phosphorus, 2, 229, 1973. Garibina, V.A., Dogadina, A.V., Zakharov, V.I., lonin, B.I., and Petrov, A.A., (Haloethynyl)phospho-nates. Synthesis and electrophihc reactions of (chloroethynyl)phosphonic esters, Zh. Obshch. Khim., 49, 1964, 1979 J. Gen. Chem. USSR (Engl. Transl.), 49, 1728, 1979. 

Shaw, M.A., and Ward, R. S., Addition reactions of tertiary phosphorus compounds with electrophilic olefins and acetylenes, in Topics in Phosphorus Chemistry, Vol. 7, John Wiley Sons, New York, 1972, pp. 1-36. 

In all of this early work the general observation was made that the successful operation of the process was greatly interfered with by the rapid deterioration of the catalyst. This seemed to depend in part upon impurities present in the acetylene (phosphorus and its compounds being particularly potent poisons) and also upon the deposit of carbon on the surface of the catalyst due to decomposition reactions. When metal oxides or compounds such as, for example, molybdic acid were used, deterioration appeared to be due at least in part to the partial reduction of these compounds. In most of these cases the activity of the catalyst was restored 107 by heating it in a current of air at high temperatures (600° C.). 

Peroxides, organic Phosphorus (white) Potassium chlorate Potassium perchlorate Potassium permanganate Silver Acids (organic or mineral), avoid friction, store cold Air, oxygen Acids (see also chlorates) Acids (see also perchloric acid) Glycerol, ethylene glycol, benzaldehyde, sulphuric acid Acetylene, oxalic acid, tartaric acid, fulminic acid (produced in ethanol — nitric acid mixtures), ammonium compounds... 

Mercury(II) cyanide Mercury(I) nitrate Mercury(II) nitrate Fluorine, hydrogen cyanide, magnesium, sodium nitrite Phosphorus Acetylene, aromatics, ethanol, hypophosphoric acid, phosphine, unsaturated organic compounds... 

Of all the reactions studied, only the synthesis of nitrogen oxides and acetylene in arcs or plasma torches and that of ozone in glow and corona discharges are of major importance. In addition, a few small-scale preparations of inorganic compounds have been developed, e.g. synthesis of hydrazine and of hydrides and halides of silicon, germanium, tin, lead, phosphorus or arsenic 3> ... 

Organic constituents that may be found in ppb levels in WP/F smoke include methane, ethylene, carbonyl sulfide, acetylene, 1,4-dicyanobenzene, 1,3-dicyanobenzene, 1,2-dicyanobenzene, acetonitrile, and acrylonitrile (Tolle et al. 1988). Since white phosphorus contains boron, silicon, calcium, aluminum, iron, and arsenic in excess of 10 ppm as impurities (Berkowitz et al. 1981), WP/F smoke also contains these elements and possibly their oxidation products. The physical properties of a few major compounds that may be important for determining the fate of WP/F smoke in the environment are given in Table 3-3. 

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