Sciencemadness Discussion Board

diphenyl ether

Vogelzang - 23-4-2009 at 04:55

Does anyone here know how safe diphenyl ether (aka phenyl ether or diphenyl oxide) is as far as developing peroxides? You can test ethers for peroxides using KI solution and reduce them use FeSO4 or other reducing agent.

grind - 23-4-2009 at 06:40

Diphenylether should be absolutely safe concerning peroxides. I´ve read alot about peroxides in organic compounds and never heard anything that diphenylether is affected by that. Another fact, diphenylether does not possess an alpha-H, so peroxid-development shouldn´t be possible.

Vogelzang - 23-4-2009 at 15:37

diphenyl ether is given a (3) rating (may also form peroxides) here: http://policies.anu.edu.au/attachments/714

Strangely enough, it may be used as a stabilizer when distilling other ethers according to
US 2254404 Distillation of ethers containing peroxides
page 1 column 2 line 43 diphenyl oxide as stabilizer

http://www.pat2pdf.org
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From Google books

Perfumery synthetics and isolates - Page 193
by Paul Z. Bedoukian - Perfumes, Synthetic - 1951 - 488 pages
Weight 170.20 Diphenyl oxide has been used by perfumers for many years because
of its strong geranium odor. It has a somewhat crude odor, however, ...
Since diphenyl oxide is an ether, it is extremely stable under all conditions
encountered in the soap, perfume, or cosmetic industry.


[Edited on 23-4-2009 by Vogelzang]

Ozone - 23-4-2009 at 17:04

It may form peroxides but, following scission (homolytic cleavage), can stabilize multiple radicals by delocalizing them within the pi system of each ring.

Cheers,

O3

grind - 24-4-2009 at 02:51

Quote: Originally posted by Vogelzang  

Strangely enough, it may be used as a stabilizer when distilling other ethers
[Edited on 23-4-2009 by Vogelzang]

I think it is rather a dilution agent than a stabilizer in this case. DPE is not as volatile as the usual ethers used as solvents and dilutes the peroxides which remain after distillation of the ethers. A diluted solution of peroxides is not as explosive as the neat peroxides are.
Of course you can substitute DPE, a lot of less volatile compounds are suitable for this purpose.

Eclectic - 24-4-2009 at 22:36

http://www.dow.com/heattrans/prod/synthetic/dowtherm.htm
:cool:

Vogelzang - 25-4-2009 at 09:05

US 1882809 Composition of matter
diphenyl oxide & diphenyl eutectic diagram

US 1899257 Process for the purification of diphenyloxide

US 1746977 Electrical apparatus

Vogelzang - 25-4-2009 at 09:28

SOME PROPERTIES OF PHENYL ETHER.
Alfred N. Cook
J. Am. Chem. Soc., 1904, 26 (3), 302-304

Attachment: ja01993a011-phenylether.pdf (185kB)
This file has been downloaded 928 times

[Edited on 25-4-2009 by Vogelzang]

Vogelzang - 25-4-2009 at 15:06

Danger of explosion: Product does not present an explosion hazard.
http://www.alfa.com/content/msds/USA/A15791.pdf

Some links/sources say that diphenyl ether can form explosive mixtures with air, for example:
http://www.fileden.com/files/2008/8/24/2063601/chemistry/JCE...

Vogelzang - 26-4-2009 at 08:45

STUDIES IN AUTO-OXIDATION REACTIONS. II. THE MECHANISM OF THE AUTO-OXIDATION OF CERTAIN ETHERS
Nicholas A. Milas
J. Am. Chem. Soc., 1931, 53 (1), 221-233
http://www.fileden.com/files/2008/8/24/2063601/chemistry/ja0...

THE CHEMISTRY OF THE DIARYL ETHERS
http://www.fileden.com/files/2008/8/24/2063601/chemistry/cr6...

http://www.pat2pdf.org

US 2254404 Distillation of ethers containing peroxides
high boiling hydrocarbon oil as stabilizer

US 2790813 Safe recovery of tetrahydrofuran vapors

US 3003002 Purification of ether
anion exchange resin, KI test for peroxides

US 2552670
reduction of peroxides in cyclic ketones
col. 1 lines 42+
In accordance with the present invention, the peroxides are removed from the oxidation effluent by treatment with an aqueous solution of a reducing agent, such as a ferrous salt, a stannous salt, a chromous salt, a sulfite, or a bisulfite, that reduces peroxides.

US 2563598
removal of peroxides and similar unstable oxy-compounds from mixtures of hydrocarbons and oxygenated organic compounds

US 3420906 REMOVAL OF PEROXIDES FROM A CYCLOHEXENE STREAM
silica gel

US 2526499 Refining heavy oils
Col. 2 lines 13+
It has now been discovered that peroxides can be substantially completely removed from higher boiling fractions of petroleum by contacting them with a bleaching earth such as Attapulgus clay, Floridin, fuller's earth, Olmstead clay, etc., at temperatures between 60' and 120' F., preferably between 70 and 90 F.

US 2058250 Treatment and packaging of ether

http://www.chemistry.ohio-state.edu/ehs/peroxide.htm


From Organic Solvents:

Ethers form peroxides under normal storage conditions. Unless a test shows peroxides to be absent, ethers should not be evaporated or distilled to near dryness. The rate of formation of peroxides in a given ether depends on the storage conditions. Peroxide formation is accelerated by heat, light and air. A small amount of moisture will accelerate peroxide formation in most ethers. Ethers kept in the laboratory should be in a dark bottle in an atmosphere of nitrogen in contact with iron filings or copper powder. Storage in a refrigerator is further recommended.

Peroxide formation in isopropyl ether is rapid. It is advisable to test for peroxide formation, even though it had been freed of them only a short time before.

Unstabilized isopropyl ether readily forms peroxides and may detonate upon shaking. Isopropyl ether can be stabilized by .001% w of dihydric phenols such as pyrocatechol, resorcinol or hydroquinone. Commercial isopropyl ether is usually stabalized with para benzylamimophenol. Peroxides can be destroyed with sulfite solution. Storage in steel containers inhibits the formation of peroxides. Further information on the subject of peroxides in isopropyl ether can be found in J Chem Eng Data, 5, 383 (1960). The preparation of isopropyl ether using ascarite clay catalyst was published in Zh Obshch Khim 19, 348 (1949); CA 44 1006 (1950)


[Edited on 26-4-2009 by Vogelzang]

Sandmeyer - 9-5-2009 at 19:49

Quote: Originally posted by Ozone  
It may form peroxides.

Cheers,

O3


How? The ipso carbon is quaternary...