Seven PHOSPHORUS COMPOUNDS

The first seven-coordinate phosphorus compound, 12, containing a spiro phosphorus atom has recently been reported <2000IC1338>. The IUPAC recommendations for the nomenclature of spiro compounds was revised and extended in 1999 <1999PAC531>. 

There is some indication that the phosphorus oxychloride formed in the preparation of the acid chloride interferes with the cyclization when aluminum chloride is used. Thus, the cyclization of a/y-diphenylbutyrio acid was effected in 94% yield only after the volatile phosphorus compounds had been removed from the reaction mixture -otherwise the yield was only 77%.114 By removing the phosphorus oxychloride under reduced pressure before introduction of the aluminum chloride,114 115 114 seven acids have been cyclized in yields of 85% or better. No single set of directions can be given which is entirely general. The following description of the cyclization of a/y-diphenylbutyric acid is a typical example of the form of procedure. The critical phase of the reaction is during the aluminum chloride treatment the optimum time and temperature may vary for each add. 

In view of the fascinating potential of phosphorus compounds, it is of substantial interest to develop a deeper understanding and presentation of their chemistry. In this volume leading scientists present modern research trends in seven comprehensive reviews providing a deep insight into the specific subjects. 

SCF calculations for the hypothetical compound H3PO were carried out by Marsmann et al.. The authors studied the effect of adding either a c/ or another p orbital to a phosphorus atom depicted in terms of seven s and three p Gaussian orbitals. An approximate model of H3PO based on the valence bond method has been published by Mitchell. ... 

The majority of gold(I) ylide complexes prepared have been of a binu-clear constitution. The first compound of this type was obtained (56) when [Au(CH2PMe3)2]Cl was allowed to stand in the presence of the ylide for seven days [Eq. (19)]. The 3IP-NMR spectrum showed only one signal, indicating that the two phosphorus centers were in identical environments, and the H-NMR spectrum exhibited two doublets with 2/(P—CH3) and 2J(P—CH2) having the same sign. Thus the symmetrical structure depicted in Eq. (19) was invoked, and the presence of two onium centers adjacent to the Au—C bonds was believed to stabilize this unlikely species. 

The apparatus and procedure for the preparation of 2-chloroethyl dichlorophosphite are essentially the same as described for the analogous silicon and sulfuryl compounds (synthesis 30). One hundred thirty-seven and one-half grams of reagent-grade phosphorus (III) chloride (1.0 mol) is allowed to react with 80.5 g. of freshly distilled, anhydrous ethylene chlorohydrin (1.0 mol) in a 500-ml. flask under the conditions set forth in the cited synthesis. Approximately 1 hour is required for the introduction of the ethylene chlorohydrin. 

Matches without Sulphur, which can be ignited by friction on any surface and do not absorb moisture from the air, are prepared by dipping the matches into a hot solution of any kind of fat, and using the following inflammable compound Seven parts of phosphorus, 7 of gum-Arabic, 40 or lead nitrate, 5 of pulverized glass, and 10 of water. 

Methods to synthesize seven-membered rings containing phosphorus were previously described in CHEC-II(1996) <1996CHEC-II(9)947>. Herein, we report new synthetic approaches to these compounds that appeared in the literature after 1995. 

Azaphosphirene complexes of W or Mo react with acetylenedicarboxylates yielding phosphirane complexes incorporated into cage compounds <20070M1371>. Mo(CO)4PMe3-complexed phosphiranes and phosphirenes are smoothly decomplexed under mild CO-pressure <2006OM5286>. A further study deals with the intramolecular phosphinidene addition to the C=C bond of Mo complexed, seven-membered phosphorus heterocyles to afford bidentate phosphorus baskets <2006CEJ4333>. 

This paper describes the electrophilic ring-opening polymerization of seven new cyclic phosphorus(III) compounds, 1-7. The polymerization of five- and slx-membered deoxophostones, 1 and and of a benzoxaphosphole 2, produced poly (phosphine oxldejs 11, and via Arbuzov type reactions. The polymerization of f e and slx-" membered deoxothlolphostones, 4 and 5, gave poly(phosphine... 

The mass spectra of a number of heterocyclic compounds have been reported. The fragmentation patterns of thiophosphoryl derivatives of phosphorinanes are sensitive to stereochemistry, thus for the series (95) facile loss of the HS radical is indicative of an axial PS bond. The seven-membered heterocycles (96 Ch = S, Se) undergo a remarkable migration of sulphur or selenium from phosphorus to carbon with ring cleavage. While exocyclic P-C bonds of five-and six-membered heterocycles in the phosphonic class may be readily cleaved with retention of the phosphorus ring system, the seven-membered ring (97) exhibits facile expulsion of a phosphorus radical. ... 

When the previous acid is evaporated on the water-bath with seven parts of fuming nitric acid, nitration takes place m the meinitro-acid forms pale yellow needles, M.pt. 174° C., and is less soluble in water than the corresponding para-compound. The barium and calcium salts are yellow, microcrystalline powders. Reduction of the mtro-acid yields the amino-acid as brownish needles, softening at 280° to 300° C. and decomposing at higher temperatures the barium and calcium salts are reddish-brown powders. o-Carboxyphenylphosphinic acid,... 

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