Phosphoryl tribromide

J(PQ) and J(PN)). Trends in J(P170) have been used to study the protonation of phosphoryl tribromide, phosphoryl trifluoride and dif1uorophosphoric acid. Nitric acid had a greater protonation power than Hammett acidity functions indicated.77 This coupling has been the subject of a semiempirical sum over states theoretical study.7 ... 

Zyk et al. <2000RJ0794> reported the synthesis of fused-ring thietanes by the reaction of the bis-morpholine sulfide-phosphoryl trihalide complex 85 with norbornadiene. The formation of 4-thiatricyclo[3.2.1.03,6]octane 86 was demonstrated and yields varied slightly depending on the phosphoryl trihalide used. When phosphoryl trichloride was used, the yield was 69% in the case of phosphoryl tribromide, it was 72%. The complex 84 was obtained by the reaction of the bis-morpholine sulfide with phosphoryl trihalide in dichloromethane at —40°C (Scheme 15). The same authors <1996RCB2393> performed a similar reaction of norbornadiene with bis-morpholine disulfide-phos-phoryl tribromide complex 87, which led to the formation of the same thietane 86 in 63% yield (Scheme 15). These reactions have also been described by Robin and Rousseau in a review <2002EJ03099>. 

Condensation of anilines with ethyl 4,4,4-trifluoroacetoacetate have been established to give the corresponding 4,4,4-tiifluoro-3-oxobutane substituted anilides, precursors in the synthesis of 4-(trifluoro-methyl)-2-quinolinones 111 [84], Heating of these compounds with phosphoryl tribromide affords 2-bromo-4-(trifluoro-methyOquinolines which can be converted into 4-(trifluoromethyl) quinolines 110 by reductive debromination (Scheme 55) [85]. 

Hydroxyalkylthiazoles are also obtained by cyclization or from alkoxyalkyl-thiazoles by hydrolysis (36, 44, 45, 52, 55-57) and by lithium aluminium hydride reduction of the esters of thiazolecarboxylic acids (58-60) or of the thiazoleacetic adds. The Cannizzaro reaction of 4-thiazolealdehyde gives 4-(hydroxymethyl)-thiazole (53). The main reactions of hydroxyalkyl thiazoles are the synthesis of halogenated derivatives by the action of hydrobroraic acid (55, 61-63), thionyl chloride (44, 45, 63-66), phosphoryl chloride (52, 62, 67), phosphorus penta-chloride (58), tribromide (38, 68), esterification (58, 68-71), and elimination that leads to the alkenylthiazoles (49, 72). 

In view of the high price and other difficulties associated with the use of phosphoryl bromide, the transhalogenation of 2-chloro- and 2-chloro-4,6-dimethyl-pyrimidine (919) by treatment with inexpensive phosphorus tribromide to give their bromo analogues in >50% yield, assumes potential importance as a general method (67JCS(C)1204). 

Phosphorus tribromide and bromine 191 Phosphorylated deoxy sugar acids. . 88... 

Using Phosphorus Tribromide, Phosphorus Pentabromide, or Phosphoryl Bromide... 

Arsenic triiodide also dissolves, the saturated solution at 15° C. having density 3-661. Other soluble halides are potassium bromide, anhydrous ferric and aluminium chlorides 6 and tetramethyl ammonium iodide but the iodides of rubidium, cadmium, manganese and cobalt, also mercuric and stannic iodides, and cobalt and stannic bromides, are insoluble or only very slightly soluble in arsenic tribromide. The liquid also dissolves phosphoryl bromide and, very slightly, ammonium thiocyanate. In the mixed solutions of halides, the components may react chemically (cf. p. 106), but such is not always the case for example, with antimony tribromide a continuous series of solid solutions is formed.7... 

He found that with ordinary commercial red phosphorus with 98 per cent, phosphorus, there dissolved 0-056 and 0-108 per cent, of phosphorus in respectively 10 and 42 hrs., and with a finely-divided sample 0-092 and 0-116 percent, phosphorus in 10 and 20 hrs. respectively. R. Schenck found that 100 grms. of phosphorus tribromide dissolved 0-2601 grm. of scarlet phosphorus at 172°, and 0-3634 grm. at 184°. E. Baudrimont showed that yellow phosphorus does not attack phosphoryl bromide at the b.p. L. Rosenstein found that soln. of arsenates, and arsenic, antimony, or bismuth salts are not reduced by boiling with red phosphorus but W. Finkelstein found that a nitrobenzene soln. of arsenic trichloride is reduced by yellow phosphorus and arsenic is deposited. 0. Ruff observed that phosphorus reacts with antimony trichloride in the presence of a little aluminium chloride. F. E. Brown and J. E. Snyder observed that vanadium oxytrichloride is without action on red or white phosphorus. 

A. Michaelis did not succeed in making pyrophosphoryl bromide, P203Br4, by the action of nitrogen peroxide or trioxide on phosphorus tribromide—the products are phosphorus pentoxide and phosphoryl bromide. T. E. Thorpe and A. E. H. Tutton said metaphosphoryl bromide, P02Br, is produced by the action of bromine on phosphorous oxide as indicated above, and it remains as a residue after the phosphoryl bromide has been removed by distillation. 

Nonmetal Halides. Vigorous or explosive reactions occur with phosphorus tribromide on addition of drops of water,20 phosphorus trichloride, phosphorus pentachloride,21 diselenium dichloride,22 sulfur dichloride, boron tribromide, sulfur dibromide,17 seleninyl bromide,23 phosphoryl chloride, sulfinyl fluoride, silicon tetrachloride, and silicon tetrafluoride.24... 

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