Talk:Phenols

Untitled
i just wanted to know the effect of the OH group on the reactivity of the benzene ring in phenols? —Preceding unsigned comment added by Tanu786 (talk • contribs) 16:30, 23 September 2010 (UTC)

I have one doubt, this phenol is not completely miscible in water, then how the scientists are making a solution of phenol for experimental analyis,say, particular ppm for degradation analyis. please clarify my doubts

vijaya kumar V,

Dept of chemical engineering, IIT Bombay, Mumbai-400076,

India, Thanking you,
 * In response to Vijaya, I have recently made a solution of 80 %(w/w) phenol (crystalline) in water with no problems.


 * About the page, should we have the hydroxycinnamic acids added to the list on this page eg ferulic acid, coumaric acid and vanillic acid/vanillin. The former don't seem to have pages, but vanillin does, and I would count that as a phenolic.  Terri G 11:32, 10 April 2006 (UTC)

Introduction copied
I'm not sure why the last person to comment (in the history) was bothered about the introduction being copied, seeing as it's an open licence. Terri G 10:11, 6 September 2006 (UTC)

good day!

Im an inefction control nurse in a hospital, how do I know that a particular disinfectant contains phenol? thank you!

O-alkylation of phenos
When phenol reacts with ethyl iodide in the presence of aqueous sodium hydroxide and heat, it forms ethy phenyl ether or phenetole. What happens to the iodine? Is it converted to any by-product? If yes, then what is it?

Thanks Divya (SYBSc student)

P.S. We were told about two years back that if HI (in any form) is formed in any organic reaction, it is unstable. So that is why this question cropped up.

Iron(III) choride test
There should be some information on the test for phenols. A neutral iron(III) choride solution will turn purple when it is added to phenol and its derivatives. Lmatt (talk) 21:27, 10 June 2009 (UTC)

Need for further concerted editing
This document is extraordinarily weak, relative to the richness of the subject, and needs expert attention. Prof D

Meduban (talk) 20:41, 15 February 2011 (UTC)

Where we stand
Today I merged the content of the natural phenols article into this one. That article was badly sourced and essay-like - basically it is all WP:OR. I am taking a break from this now and want to get some feedback while I am gone. The "occurrences" section is a cherry-picked, random laundry list, rather than something useful and encyclopedic. And it is way too long, giving that section undue weight. This is the result of prior editors using primary sources instead of following secondary and tertiary sources which is exactly what WP:OR warns against. So here is my question - namely, how to reorganize that section (using secondary sources of course). We could organize it by the phenolic compounds themselves, discussing just the most common ones, where they are found, and what their role is. (Or the same but classes of phenolic compounds)  Or we could focus on roles, and have just a few examples of the phenolic compounds and what organism use them for each role. Or something else. What do you think? Jytdog (talk) 00:23, 3 March 2013 (UTC)


 * Is listing the occurrences even necessary? It does add a lot of bulk/fluff to the article.  (I can see listing the what phenol was a component of when it was first discovered, but that's already covered in the phenol article.)  Stating that so-and-so organism uses/produces/excretes a very specific phenol that already has its own Wiki page just seems like a waste of space in my opinion.  The roles sections were at least informative and interesting (and read much less like a list!), but I'm not sure if that has any bearing on whether or not something should be on Wikipedia.  Zaryn (talk) 02:06, 1 April 2013 (UTC)


 * Thanks for weighing in! We are on the same page there and I will probably take that stuff out if you don't beat me to it.  btw, while I am sure you had good intentions in editing my post above, that was bad form... you are always free to edit the article but you should not mess with what somebody else writes on a Talk page. see WP:TPO Jytdog (talk) 03:20, 1 April 2013 (UTC)


 * My apologies! I've skimmed WP:TPO before but must've completely missed that bit.  I'll let you remove the fluff, since I'd be tempted to do some major hack and slashing.  Would it be appropriate to create a separate list page for naturally-occurring phenols?  Or should they just be removed and leave it at that?  Zaryn (talk) 19:56, 3 April 2013 (UTC)


 * Its OK, now you know!  I am not a fan of list pages, but you are free to create one, of course.   Be careful to avoid creating content is not encyclopedic, though -- see WP:NOT Jytdog (talk) 12:01, 9 April 2013 (UTC)


 * I found the style manual for stand-alone lists: WP:SAL. I'll read it over well (no skimming!) and then try to determine if creating the list would be appropriate. Zaryn (talk) 15:06, 9 April 2013 (UTC)


 * This morning I broke the table of phenol compounds into two lists, one for naturally occurring and the other for synthetic (there was already a drug table). I was thinking about taking some of the content out of the "occurrences" section and just adding it to the table, as a starting point. But I want some sense of order or reasoning... which was the reason for my initial inquiry above.  It is useful to have some examples but there are too many now, we agree.  btw there is an editor called "NotWith" who is responsible for a lot of the content on these pages... his/her edits are... difficult. Lots of OR, and the kind of shotgun random listing of stuff like we are discussing now.  Gotta give kuodos to NotWith for generating content but it is problematic.   You may have noticed that he/she came around last night/this morning and restored content that I had deleted a while back.. which I re-deleted.  Hoping that NotWith shows up here so we can talk. 15:16, 9 April 2013 (UTC)


 * I just saw all of the edits -- yikes! Not sure if you noticed but NotWith seems to be the only active member of WikiProject Natural phenols and polyphenols, which at one point was considered for deletion and is now in userspace.  Part of the "to do" list was to identify sources of phenols, which might explain the huge revert by NotWith.  I'll leave a note on their talk page and invite them to come chat with us.Zaryn (talk) 16:05, 9 April 2013 (UTC)

Removal of cinnamic acid?
Cinnamic acid is listed in this section, but I get the sense from sources like PMID 19425182 that cinnamic acid tends to be caught up in organic acid purifications but is considered a non-phenolic compound. Consider removal? &mdash; soupvector (talk) 19:09, 25 January 2018 (UTC)
 * It's certainly a phenol, structure here, and is present in many plant food sources (particularly berries), such as this PMID 26778456. --Zefr (talk) 20:13, 25 January 2018 (UTC)
 * I'm familiar with the structure of cinnamic acid. What definition of "phenol" are you using? The abstract of the source you cited does not call cinnamic acid a phenol - does it do so in the text? The source I cited specifically says that cinnamic acid is a non-phenolic compound (since there is no hydroxyl group attached directly to the aromatic ring). &mdash; soupvector (talk) 21:56, 25 January 2018 (UTC)
 * I see your point in light of cinnamic acid being classified as a carboxylic acid here, despite its phenolic ring and the many hydroxycinnamic acids often grouped as phenolic acids (a category of polyphenols common in pigmented plant foods), such as caffeic acid and ferulic acid which, with cinnamic acid, have been called "phenolics" in literature I've seen. Strictly speaking, because the hydroxyl group is not directly attached to the phenolic ring, it is not a phenol as identified in the lede of the cinnamic acid page. --Zefr (talk) 22:37, 25 January 2018 (UTC)
 * Thanks, but there's no "phenolic ring" in cinnamic acid - perhaps you're thinking of a "benzene ring" or (more likely) "phenyl ring"? Note that phenol = phenyl + alcohol. &mdash; soupvector (talk) 23:13, 25 January 2018 (UTC)

List of occurrence of phenols is not reasonable
''For starters: I am pretty sure that thousands, maybe tens of thousands of phenols are known. So this article cannot list all of them, much less cite them and describe them. The following excerpt is representative of the problem. It is almost exclusively supported by primary references. We probably need to remove it:commented out <!--''

Orobol can be found in Streptomyces neyagawaensis (an Actinobacterium). Phenolic compounds can be found in the cyanobacterium Arthrospira maxima, used in the dietary supplement, Spirulina. The three cyanobacteria Microcystis aeruginosa, Cylindrospermopsis raciborskii and Oscillatoria sp. are the subject of research into the natural production of butylated hydroxytoluene (BHT), an antioxidant, food additive and industrial chemical.

The proteobacterium Pseudomonas fluorescens produces phloroglucinol, phloroglucinol carboxylic acid and diacetylphloroglucinol. Another example of phenolics produced in proteobacteria is 3,5-dihydroxy-4-isopropyl-trans-stilbene, a bacterial stilbenoid produced in Photorhabdus bacterial symbionts of Heterorhabditis nematodes.

Occurrences in fungi
Phenolic acids can be found in mushroom basidiomycetes species. For example, protocatechuic acid and pyrocatechol are found in Agaricus bisporus as well as other phenylated substances like phenylacetic and phenylpyruvic acids. Other compounds like atromentin and thelephoric acid can also be isolated from fungi in the Agaricomycetes class. Orobol, an isoflavone, can be isolated from Aspergillus niger.

Aromatic alcohols (example: tyrosol) are produced by the yeast Candida albicans. They are also found in beer. These molecules are quorum sensing compounds for Saccharomyces cerevisiae.
 * in yeasts

Aryl-alcohol dehydrogenase uses an aromatic alcohol and NAD+ to produce an aromatic aldehyde, NADH and H+.
 * Metabolism

Aryl-alcohol dehydrogenase (NADP+) uses an aromatic alcohol and NADP+ to produce an aromatic aldehyde, NADPH and H+.

Aryldialkylphosphatase (also known as organophosphorus hydrolase, phosphotriesterase, and paraoxon hydrolase) uses an aryl dialkyl phosphate and H2O to produce dialkyl phosphate and an aryl alcohol.

Occurrences in lichen
Gyrophoric acid, a depside, and orcinol are found in lichen.

Occurrence in algae
The green alga Botryococcus braunii is the subject of research into the natural production of butylated hydroxytoluene (BHT), an antioxidant, food additive and industrial chemical.

Phenolic acids such as protocatechuic, p-hydroxybenzoic, 2,3-dihydroxybenzoic, chlorogenic, vanillic, caffeic, p-coumaric and salicylic acid, cinnamic acid and hydroxybenzaldehydes such as p-hydroxybenzaldehyde, 3,4-dihydroxybenzaldehyde, vanillin have been isolated from in vitro culture of the freshwater green alga Spongiochloris spongiosa.

Phlorotannins, for instance eckol, are found in brown algae. Vidalenolone can be found in the tropical red alga Vidalia sp.

Occurrences in vascular plants
Phenolic compounds are mostly found in vascular plants (tracheophytes) i.e. Lycopodiophyta (lycopods), Pteridophyta (ferns and horsetails), Angiosperms (flowering plants or Magnoliophyta) and Gymnosperms (conifers, cycads, Ginkgo and Gnetales).

In ferns, compounds such as kaempferol and its glucoside can be isolated from the methanolic extract of fronds of Phegopteris connectilis or kaempferol-3-O-rutinoside, a known bitter-tasting flavonoid glycoside, can be isolated from the rhizomes of Selliguea feei. Hypogallic acid, caffeic acid, paeoniflorin and pikuroside can be isolated from the freshwater fern Salvinia molesta.

In conifers (Pinophyta), phenolics are stored in polyphenolic parenchyma cells, a tissue abundant in the phloem of all conifers.

The aquatic plant Myriophyllum spicatum produces ellagic, gallic and pyrogallic acids and (+)-catechin.

Occurrences in Monocotyledons
Alkylresorcinols can be found in cereals.

2,4-Bis(4-hydroxybenzyl) phenol is a phenolic compound found in the orchids Gastrodia elata and Galeola faberi.

Occurrences in non-vascular plants
Phenolics can also be found in non-vascular land plants (bryophytes). Dihydrostilbenoids and bis(bibenzyls) can be found in liverworts (Marchantiophyta), for instance, the macrocycles cavicularin and riccardin C. Though lignin is absent in mosses (Bryophyta) and hornworts (Anthocerotophyta), some phenolics can be found in those two taxa. For instance, rosmarinic acid and a rosmarinic acid 3'-O-β-D-glucoside can be found in the hornwort Anthoceros agrestis.

Occurrences in insects
The hardening of the protein component of insect cuticle has been shown to be due to the tanning action of an agent produced by oxidation of a phenolic substance forming sclerotin. In the analogous hardening of the cockroach ootheca, the phenolic substance concerned is 3:4-dihydroxybenzoic acid (protocatechuic acid).

Acetosyringone is produced by the male leaffooted bug (Leptoglossus phyllopus) and used in its communication system. Guaiacol is produced in the gut of Desert locusts, Schistocerca gregaria, by the breakdown of plant material. This process is undertaken by the gut bacterium Pantoea agglomerans. Guaiacol is one of the main components of the pheromones that cause locust swarming. Orcinol has been detected in the "toxic glue" of the ant species Camponotus saundersi. Rhynchophorus ferrugineus (red palm weevil) use 2-methoxy-4-vinylphenol for chemical signaling (pheromones). Other simple and complex phenols can be found in eusocial ants (such as Crematogaster) as components of venom.

Occurrences in mammals
In female elephants, the two compounds 3-ethyl phenol and 2-ethyl 4,5 dimethylphenol have been detected in urine samples. Temporal glands secretion examination showed the presence of phenol, m-cresol and p-cresol (4-methyl phenol) during musth in male elephants.

p-Cresol and o-cresol are also components of the human sweat. P-cresol is also a major component in pig odor.

4-Ethylphenol, 1,2-dihydroxybenzene, 3-hydroxyacetophenone, 4-methyl-1,2-dihydroxybenzene, 4-methoxyacetophenone, 5-methoxysalicylic acid, salicylaldehyde, and 3-hydroxybenzoic acid are components of castoreum, the exudate from the castor sacs of the mature North American beaver (Castor canadensis) and the European beaver (Castor fiber), used in perfumery. -->

Start over
''If anyone has advice on how to make this article more useful and more readable, please say so. Otherwise, my inclination is to start over. Maybe: --Smokefoot (talk) 15:02, 12 April 2018 (UTC)
 * general properties of phenols: acidity, bond strengths (anti-oxidant), reactions with electrophiles
 * synthesis and biosynthesis of phenols: with ref to phenol plus P450 hydroxylations etc
 * prominent phenols in nature and industry: tyrosine, phenylpropanoids, bisphenol A, that kind of thing.''
 * I agree that something needs to be done, a contents lists that so long that I have to scroll through it is a bad sign. There are several large lists of phenolic compounds can obviously go (who reads such things) but the tone of the article may prove tricky, it's as if two pages were written on phenols from chemistry and biology viewpoints and then shuffled together like two packs of cards - the result is disjointed. I can help with the chemistry but I'm note sure what to so about some of the biology. --Project Osprey (talk) 15:03, 16 April 2018 (UTC)

Classification
The article refers to a classification system ending with a colon implying that some type of description of that system should follow. I doesn't. Instead there is a list of examples of phenolic compounds mainly described by their trivial, non-systematic names. A short description of one or several classification systems should be welcomed, but as long as it is not provided the colon should be be replaced by period.

A list of more ore less common compounds belonging to the class of phenols (with trivial and systematic names) is certainly good to include in the article, but perhaps under the heading examples rather than under classification. The list deserves to be extendes (e.g. cresols, cathechol, hydroquinone etc, what about aromatic hydroxy compound not based on benzene, e.g. naphtol are they phenols?) More on the properties and reactions of phenols is also desirable.150.227.15.253 (talk) 14:27, 19 February 2020 (UTC)