Sciencemadness Discussion Board - Nomenclature - group abbreviations

Nomenclature - group abbreviations

The Volatile Chemist - 6-7-2014 at 14:28

Often, things like Ethyl Acetate are abbreviated EtOAc. Does anyone happen to have a list of the common abbreviations? I think they ought to be standardized. Silly, I know, but I at least want to have one standard out there as to make those abbreviations official - ish.
I'd rather not have opinions on this endeavor, but I wouldn't mind if you all posted the ones you use. I use Ac for acetate and Et for ethane, Me for methane, Pro for propane, Bu for butane, and Iso for ProO, but that's about it. What do you all use?
A list, once compiled, will be available at http://ptp.x10.mx/chemabbrv.txt
Thanks!
Nathan

aga - 6-7-2014 at 14:40

Would it not make sense to have them in capitals, or curly brackets or something ?

AlOH is silly.

[Al]OH is less silly, but looks ionic,
{Al}OH even,
or Al&OH

I like the last one best. Ampersand is probably unused in chemistry so far.

[Edited on 6-7-2014 by aga]

The Volatile Chemist - 6-7-2014 at 14:55

Quote: Originally posted by aga

Would it not make sense to have them in capitals, or curly brackets or something ?

AlOH is silly.

[Al]OH is less silly, but looks ionic,
{Al}OH even,
or Al&OH

I like the last one best. Ampersand is probably unused in chemistry so far.

[Edited on 6-7-2014 by aga]

I was thinking ' symbol before it or after it, or maybe the ` symbol. & looks too much like programming. Were you saying Al as in aluminum, or some organic thing?

arkoma - 6-7-2014 at 15:01

I use "DMK" a lot in my own notes--Dimethyl Ketone=acetone

ScienceHideout - 6-7-2014 at 19:45

Quote: Originally posted by The Volatile Chemist

Pro for propane,
Nathan

Interestingly enough, I believe that the IUPAC actually supports such nomenclature. EtOH is a lot easier formula for ethanol than CH3CH2OH. However, I just wanted to correct you on one thing...

Pr is propyl- there is no 'o' after it. Propanol is PrOH, not ProOH. Then the O would be too redundant

By the way, there are quite a few. Butyl is Bu, Aryl is Ar, etc.

Brain&Force - 6-7-2014 at 19:55

I object!

PrOH is praseodymium(I) hydroxide, not propan-1-ol!

kavu - 7-7-2014 at 01:50

For isomeric alkyl side chains additional n, i or sec or tert are usually added. So we have n-BuOH, i-PrOH, tert-BuOH and so forth. Lists of these abbreviations are widely avaliable in orgo textbooks. There's no reason to try and reinvent this wheel.

[Edited on 7-7-2014 by kavu]

forgottenpassword - 7-7-2014 at 02:02

Quote: Originally posted by The Volatile Chemist

I use Ac for acetate and Et for ethane, Me for methane, Pro for propane, Bu for butane, and Iso for ProO, but that's about it.

They are all wrong. I suggest that you open a book and re-learn the basics.

Praxichys - 7-7-2014 at 05:48

All of this is pretty straightforward.

EtOH - ethyl alcohol (use this format for alcohols)
AcOH - acetic acid (use this format for carboxylic acids)
EtOAc - ethyl acetate (use this format for esters)
Et2O - diethyl ether (use format for ethers)
Ac2O - acetic anhydride (use for simple carboxylic anhydrides)

And there are the simple alkyls... Me-, Et-, n-Pr-, i-Pr-, n-Bu-, sec-Bu-, t-Bu-, etc. Don't forget Ph-, Bn-, Bz-.

Then the myriad of solvent abbreviations... DCM, TCM, THF, DMSO...

Honestly though, these things become obvious when you get through something like Org 1. Here's a start. http://www.ch.ic.ac.uk/local/organic/tutorial/Abbreviations....

The Volatile Chemist - 7-7-2014 at 06:45

Quote: Originally posted by Brain&Force

I object!

PrOH is praseodymium(I) hydroxide, not propan-1-ol!

I know! Ac is technically Actinium, but it's kind of obvious what it represents when it's negatively charged. I saw Pro once used on Wikipedia (I know, GREAT source...), so I decided to use that so no confusion could come.

Quote: Originally posted by forgottenpassword

Quote: Originally posted by The Volatile Chemist

I use Ac for acetate and Et for ethane, Me for methane, Pro for propane, Bu for butane, and Iso for ProO, but that's about it.

They are all wrong. I suggest that you open a book and re-learn the basics.

Excuse me??? According to people posting here, only some are "wrong" abbreviations, according to IUPAC, but in reality none can be "wrong", as I said I use them on my own, and asked others what they used.
I don't know why you attacked like that, either. I certainly don't try to come across as haughty on this forum, as I'm sure most people can attest. I know I don't know very much about organics, but that doesn't mean I need to "re-learn the basics". I found that statement so out-of-place that I'm still not sure if you're just trolling me, or weren't paying attention to what I posted.

I see the silliness of making yet another standard as some of you said. I certainly didn't know IUPAC accepted abbreviations. Does anyone know if they actually have a list of the accepted ones? (Thanks for the PDF above, interesting ones in there. Is THAT the standard for IUPAC, or just some common ones)
Thanks for putting up with my slight lack of knowledge in this subject.
Nathan, TVC

woelen - 7-7-2014 at 07:09

In this thread I see Ac being misused a few times (e.g. negatively charged, named acetate). Ac stands for acetyl, being the H3C-C(=O)-group.

Some common compound of this are:
- AcCl (acetyl chloride, CH3COCl)
- AcOH (acetic acid, CH3COOH)
- NaOAc (sodium acetate, CH3COONa)
- AcAc (diacetyl, a light yellow/green diketone smelling like butterscotch, CH3COCOCH3)
- AcOAc (acetic anhydride, CH3CO-O-COCH3)

As you see, Ac does not occur as a negatively charged particle Ac(-), formally it should be assigned oxidation state +1 in many of its compounds, and only the particle OAc(-) has negative charge in the acetate ion.

[Edited on 7-7-14 by woelen]

The Volatile Chemist - 7-7-2014 at 07:48

Quote: Originally posted by woelen

In this thread I see Ac being misused a few times (e.g. negatively charged, named acetate). Ac stands for acetyl, being the H3C-C(=O)-group.

Some common compound of this are:
- AcCl (acetyl chloride, CH3COCl)
- AcOH (acetic acid, CH3COOH)
- NaOAc (sodium acetate, CH3COONa)
- AcAc (diacetyl, a light yellow/green diketone smelling like butterscotch, CH3COCOCH3)
- AcOAc (acetic anhydride, CH3CO-O-COCH3)

As you see, Ac does not occur as a negatively charged particle Ac(-), formally it should be assigned oxidation state +1 in many of its compounds, and only the particle OAc(-) has negative charge in the acetate ion.

[Edited on 7-7-14 by woelen]

Interesting... I have a few old books, like Chemical Calculations, which use it like acetate. Sorry, i didn't know...

forgottenpassword - 7-7-2014 at 09:14

Quote: Originally posted by The Volatile Chemist

Quote: Originally posted by forgottenpassword

Quote: Originally posted by The Volatile Chemist

I use Ac for acetate and Et for ethane, Me for methane, Pro for propane, Bu for butane, and Iso for ProO, but that's about it.

They are all wrong. I suggest that you open a book and re-learn the basics.

You DO need to re-learn the basics.
Ac is acetyl
Me is methyl
Et is ethyl
Pr is propyl
Bu is butyl
"Iso for ProO" is nonsensical.
As I said, they are all wrong.

[Edited on 7-7-2014 by forgottenpassword]

Nicodem - 7-7-2014 at 10:03

The Volatile Chemist, first of all, these are not true abbreviations. They are the so called "shorthands" (shorthand notations, representations or formulas). Some structural groups are so common or useful that the synthetic chemists adopted some shorthand notations for them. Some of the ones you listed (Ac, Et, Me, Bu) are used and adopted shorthands that already have their assigned meaning (acetyl, ethyl, methyl, n-butyl). Essentially what forgottenpassword said is correct: you did got them wrong, because you reassigned them a different meaning (asserting ones own definition without consent is considered wrong in most cultures, science included). Also "Iso" is too close to the Latin "isomeric" prefix "iso", so you can't use that either. The shorthand notation for propane is PrH, not Pro.

The major problem with these shorthands is in that they are most commonly used in combination with chemical symbols which can be a source of confusion, because some of these shorthands actually are identical to some symbols (as it was already noted in this thread: Ac and Pr). I try to avoid using Ac and Pr in articles (an alternative to Ac is MeCO), but they are not so much a bother when they are used in organic synthesis journals (how much organic chemistry there is with praseodymium and actinium anyway?).

The other problem is in some historical confusion. For example, there is a confusion between benzyl (Bn) and benzoyl (Bz), because the older volumes of Chemical abstracts used Bn for benzoyl (or was it the opposite?).

Edit: The last pages of JOC's guidelines for authors has a list of abbreviations and shorthands. (In relation to AvBaeyer's comment bellow)

[Edited on 9/7/2014 by Nicodem]

AvBaeyer - 8-7-2014 at 20:21

I believe that the American Chemical Society has a list of "standard" (for the ACS anyway) abbreviations for a multitude of terms. This is usually published in the first issue of the year for journals such as J Med Chem, J Org Chem, etc., under instructions for authors. Perhaps this list is generally accessible at the ACS website.

AvB

Pomzazed - 13-7-2014 at 06:13

These shorthand name are quite widely accepted. They are commonly used "formula" even in the publication entity if the title is related to organic chemistry!
(So don't keep arguing AcOH is actinium(I)hydroxide

lol)

Bunches of them can be found in either
- Name Reaction Handbook (in appendix);
- Organic Chem Textbooks (they used, but most of them are regularly used as so it doesnt show abbrev table in some books!)

The short chain alkyls all have a symbol for it:
Me; Methyl
Et; Ethyl
Pr; Propyl
Bu; Butyl
which can be tailored to show isomerism like t-Bu (tert-butyl) or s-Bu (sec-butyl) (also notice the italics s and t)

The group itself also have their own representatives:
R: Alkyl group (include alkenyl and alkynyl)
Ar: Aryl group (any aromatics)
X: Halogen
(Thus, ArOH shows phenolic-like moeity and not Argon Monohydroxide

)

Many common synthesis moeities (especially if they are used alot in synthesis or as solvent) also have their own:
Ph; Phenyl
Bn; Benzyl
Bz; Benzoyl
Ac; Acetyl
Cy; Cyclohexyl
Ts; Tosyl (Toluenesulfonyl)
Bs; Brosyl (Bromophenylsulfonyl)
Tf; Triflyl (Trifluoromethylsulfonyl)
et cetera

They can be attached together with other "moeity", "radical" like:
PhH; Benzene
PhMe; Toluene
AcOH; Acetic Acid
AcOAc; Acetic Anhydride (sometimes Ac₂O; and not actinium suboxide!)
EtOAc; Ethyl Acetate
TsOH; Toluenesulfonic Acid
TsCl; Toluenesulfonyl Chloride
EtOEt; Diethyl Ether (Et₂O is also very common)
PhO-; Phenoxy anion
AcO-; Acetate anion
et cetera

Even in inorganic chemistry they also have these for ligands!
Cp; Cyclopentadienyl
Cp*; Pentamethylcyclopentadienyl (Ha! Good idea they used! the ligand looks really like a star!

)
en; ethylenediamine (as ligand, all small lettercase)
bipy; bipyridine (as ligand, also all small lettercase)

So: FeCp₂ is well known "formula" of ferrocene for inorganic chemists, and not Perferric Copernicide!

The confusion may also arise if you capture an ancient references, as at that time each publisher just choose their own shorthands, so you will see Ac both as Acetyl, Acetoxy, Acyl, etc.

But nowadays they are quite standard already...

[Edited on 13-7-2014 by Pomzazed]