7789-60-8 Usage
Chemical Properties
Phosphorus tribromide is a colourless liquid(possibly hazy) with the formula PBr3. It fumes in air due to hydrolysis and has a penetrating odour. It is widely used in the laboratory for the conversion of alcohols toalkyl bromides.
Phosphorus tribromide (PBr3) is commonly used in Hell-Volhard-Zelinsky halogenation for the α-bromination of carboxylic acids to form the corresponding acyl bromide. It is also useful for the conversion of primary and secondary alcohols to alkyl bromides.
Uses
Different sources of media describe the Uses of 7789-60-8 differently. You can refer to the following data:
1. Phosphorus tribromide is used mainly for the conversion of alcohols to alkyl bromides and it is used in tests for skin corrosivity. It is used for alkene preparation and it act as a lewis base and a lewis acid. Phosphorus tribromide is used in the manufacture of pharmaceuticals such as alprazolam, methohexital and fenoprofen.
Phosphorus tribromide may be used as a reagent:
In a novel protocol for synthesizing 7-ethoxy-1-(p-ethylphenoxy)-3,7-dimethyl-2-octene, a synthetic juvenile hormone mimic of trans,trans,cis-10,11-epoxy-7-ethyl-3,11-dimethyltrideca-2,6-dienoate.
To synthesize 1,2,3-diazaphosphinane, 1,2,3-thiazaphosphinine and 1,2-azaphosphole bearing a chromone ring.
To synthesize 1-Bromoundec-1-ene from 10-undecen-1-ol.
2. Phosphorus(III) bromide is used mainly for the conversion of alcohols to alkyl bromides and it is used in tests for skin corrosivity. It is used for alkene preparation and it act as a lewis base and a lewis acid. It is used as a catalyst for the alpha-bromination of carboxylic acids and used as intermediates in hell-volhard-zelinsky halogenation. Phosphorus tribromide is used in the manufacture of pharmaceuticals such as alprazolam, methohexital and fenoprofen. It is also used as a fire suppression agent.
Preparation
Phosphorus tribromide, PBr3, is most conveniently prepared by reaction between liquid bromine and a solution of white phosphorus in PBr3. In most of its reactions, the tribromide resembles the trichloride although the former has been much less studied and in some cases the products seem to be more complex.
Reactions
Silyl phosphites such as (EtO)2POSiMe3 and (Et3SiO)3P are known. The latter compound can be prepared in 30% yield by reacting phosphorus tribromide with an organosilane in the presence of zinc chloride. Esters of the former type can be made by reaction.
3Et3SiO+PBr3–-(Et3SiO)3+3RBr
Et3SiONa+(EtO)2PCl–-(EtO)2POSiEt3+NaCl)
General Description
A colorless fuming liquid with a pungent odor. Corrosive to metals and tissue. Boiling point 347°F (175°C). Freezing point -40°F (-40°C).
Air & Water Reactions
Fumes in air. Decomposed by water to form phosphoric acid and hydrobromic acid. Reaction with warm water is very rapid and may be violent [Mellor v.8. 1032 1940].
Reactivity Profile
Phosphorus tribromide reacts with oxidizing agents to generate heat and products that may be flammable, combustible, or otherwise reactive; the reactions may be violent. Forms complexes with potassium or sodium metal that explode when shocked. Drop wise addition to 3-phenylpropanol caused an explosion when stirring of the mixture was discontinued [Chem. Brit., 1974, 10, 101-102].
Health Hazard
Inhalation causes severe irritation of nose, throat, and lungs. Ingestion causes burns of mouth and stomach. Contact with eyes or skin causes severe burns.
Safety Profile
Probably highly toxic.
A corrosive irritant to the eyes, skin, and
mucous membranes. Wdl react with water,
steam, or acids to produce heat, toxic and
corrosive fumes. Violent reaction or ignition
with calcium hydroxide + sodium carbonate,
phenylpropanol, sulfuric acid, oleum,
fluorosulfuric acid, chlorosulfuric acid,
1,1,1 -tris(hydroxymethyl)methane, water,
potassium, sodium, RuO4. When heated to
decomposition it emits very toxic fumes of
Brand POx. See also PHOSPHIDES and
BROMIDES.
Purification Methods
It is decomposed by moisture, it should be kept dry and is corrosive. Purify it by distillation through an efficient fractionating column [see Whitmore & Lux J Am Chem Soc 54 3451] in a slow stream of dry N2, i.e. under strictly dry conditions. [Gay & Maxson Inorg Synth II 147 1946, Org Synth Col Vol II 358 1943.] Dissolve it in CCl4, dry it over CaCl2, filter and distil it. Store it in sealed ampoules under N2 and keep it away from light. HARMFUL VAPOURS.
Check Digit Verification of cas no
The CAS Registry Mumber 7789-60-8 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 7,7,8 and 9 respectively; the second part has 2 digits, 6 and 0 respectively.
Calculate Digit Verification of CAS Registry Number 7789-60:
(6*7)+(5*7)+(4*8)+(3*9)+(2*6)+(1*0)=148
148 % 10 = 8
So 7789-60-8 is a valid CAS Registry Number.
InChI:InChI=1/Br3P/c1-4(2)3
7789-60-8Relevant articles and documents
Chemical Disorder in Non-Oxide Chalcogenide Glasses. Site Speciation in the System Phosphorus-Selenium by Magic Angle Spinning NMR at Very High Spinning Speeds
Lathrop, David,Eckert, Hellmut
, p. 7895 - 7902 (1989)
The local structure of phosphorus-selenium glasses with P contents ranging from 5 to 75 atom percent P is investigated by magic angle spinning (MAS) 31P NMR.In contrast to most oxidic glass systems, P-Se glasses require very high spinning speeds (12-14 kHz) for obtaining the resolution needed to differentiate between distinct sites present in these glasses.Chemical shift assignments are based on parallel solid-state NMR investigations on the crystalline reference compounds α-P4Se3, β-P4Se3, P4Se4, and α-P4Se3I2.The solid-state NMR spectrum of P4Se4 suggests that the molecular structure of this compound is not the one previously proposed on the basis of IR spectroscopy but is rather like the selenium analogue of α-P4S4.The results obtained on P-Se glasses confirm the prominent role of P4Se3 molecular constituents in glasses containing P contents >/= 50 atom percent but also show these units are absent at lower P contents.Below 35 atom percent P, the MAS-NMR spectra are decidedly bimodal, indicating site differentiation between PSe3/2 and Se=PSe3/2 units.The compositional dependence of the peak area ratio is explained consistently in terms of a melt-equilibrium reaction between different short-range-order environments according to PSe3/2 + n>1/n -> Se=PSe3/2, with a phenomenological equilibrium constant K = 0.85 +/- 0.05 (atom fraction)-1.The near-unity value of K reflects the efficient competition of homoatomic (Se-Se) versus heteroatomic (P=Se) bond formation in P-Se glasses, hence providing a rationale for the pronounced glass-forming tendency in this system.
Preparation and spectroscopic characterization of difluorophosphorane, PH3F2. 31P NMR spectrum of protonated diphosphine, P2H5+
Minkwitz, Rolf,Liedtke, Andreas
, p. 4238 - 4242 (2008/10/08)
The preparation of difluorophosphorane, PH3F2, from the reaction of diphosphine and hydrogen fluoride is reinvestigated; it has been characterized by multinuclear (1H, 19F, 31P) NMR spectroscopy. Complete infrared and Raman low-temperature spectra of difluorophosphorane are reported. It reacts with alkali-metal fluorides to give phosphine and hexafluorophosphates(V). On the basis of 31P NMR spectroscopic results, a reaction mechanism for the formation of PH3F2 is proposed. The byproducts of the reaction were PH2F3, (PH)n, and P2H5+; the last was observed for the first time. In carbon disulfide solution, diphosphine neither reacts with hydrogen halides to yield protonated diphosphine nor interacts with hydrogen fluoride to form difluorophosphorane.
Cyano and Thiocyanato-derivatives of the Hexachlorophosphate Ion (PCl6(1-))
Dillon, Keith B.,Platt, Andrew W. G.
, p. 1199 - 1204 (2007/10/02)
The preparation and identification in solution of several new cyano- and thiocyanato-derivatives of the hexachlorophosphate (PCl6(1-)) ion are described.The cyano-complexes (1-) (n = 1-3) and the hexathiocyanatophosphate ion P(NCS)6(1-) have been isolated as tetra-n-alkylammonium salts and further characterised by elemental analysis, (31)P n.m.r., and (in some cases) vibrational spectroscopy.The mer isomer of the (1-) ion has been obtained pure and the fac isomer in a less pure state (ca. 3:1 fac:mer) by different preparative routes.Isomeric configurations in the chlorothiocyanatophosphate series (1-) have been assigned on the basis of the pairwise interaction method.
