Questions tagged [nomenclature]
This tag should be used for questions about the naming of compounds and elements, usually using systematic names according to IUPAC recommendations, but also using retained traditional names.
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What is the correct name of the compound according to IUPAC nomenclature [closed]
Which is the correct name of the compound shown in the photo attached to this, according to IUPAC nomenclature. Is it 2-Bromo-5-chloropentane or 4-Bromo-1-chloropentane. And what are the rules of ...
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What would be the correct IUPAC name of this compound? [duplicate]
How many carbon atoms will be there in the parent carbon chain? I have proposed its few names, which one is more appropriate?
4-Chloro-3-ethyl-2-(1-methylethyl)-butan-1-ol
3-(1-Chloromethyl)-2-(1-...
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Why the IUPAC naming of this compound is 6-hydroxycyclohex-2-en-1-one?
Should it not be 2hydroxycylohex-5-en-1-one?
Functional groups are usually given more priority than double/triple bonds, except in cases of Nitro, halides, etc.
Shouldn't the priority order be Ketone&...
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Protein/polypeptide nomenclature, residue number superscripted or not?
When referring to a specific residue number of a given amino acid, should the residue number be superscripted or simply affixed?
For example, When referring to a Tryptophan residue at the 147th ...
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2
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Can you write oxidation states with negative Roman numerals?
As I understand, Roman numerals are used for oxidation states, whereas Arabic numerals are used for the charge of full ions, with some ambiguity allowed when a metal centre is all but ionised, such as ...
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1
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3-Bromo-2-propylbutanal vs 2-(1-Bromoethyl)pentanal, which one is correct name according to IUPAC nomenclature standards and why?
In above example, What should should be the main chain. According to the IUPAC nomenclature standards whether it's name should be - (a) 3-Bromo-2-propylbutanal (b) 2-(1-Bromoethyl)pentanal
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Rules for numbering in unsaturated cyclic compounds according to IUPAC? [duplicate]
Below is a cyclic compound. What should be the numbering scheme for this compound while naming it according to IUPAC rules?
As per the lowest set of locants option one (3-Ethyl-2-methylcyclohexene) ...
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1
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Polycyclic or heterocyclic compound naming [closed]
What is the order and name of the following polycyclic compound?
I am studying heterocyclic chemistry to teach some notions to my high school students even if it is outside curriculum (to give them ...
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How to name ether with ketone and carboxyl groups?
Carboxylic acid is the main functional group due to higher priority, but since it's an ether, what's the proper way to name the following compound?
My attempt: 2-(1-methyl oxo propyl ether) ethanoic ...
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What is the correct way to specify the weight fraction from bulk compositional data with a listed total % (e.g. from XRF, ICP)?
TL;DR = With bulk composition results, such as from XRF or ICP, is the mass fraction of a given analyte that analyte given as a % or the analyte divided by the given total mass %?
Perhaps a silly and ...
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Nomenclature of monocyclic molecule with multiple insaturation
The PIN (Preferred IUPAC Name) of this molecule
is (Z)-cycloocta-3-en-1,5-diyne, but at first I thought it was (Z)-cycloocta-1-en-3,7-diyne, following the rules of the Blue Book, P.31.1.3
Can someone ...
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nomenclature rules: lower positions for all substitute groups or consider group names first [duplicate]
Consider the naming of:
When numbering right to left, the Br will be given 3.
When numbering left to right, the Cl will be given 3.
As they are equal, should we consider their names now (Br is ...
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1
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Why CFC naming system is so weird? [duplicate]
Why it can't be just as simple as just the number of C, H & F atoms respectively instead of (C - 1), (H+1) & F?
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4
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Does -ate suffix mean existence of -ite oxyanions?
According to online resources oxyanions are named as
Per+element+ate eg. $\ce{ClO4-}$
Element+ate eg. $\ce{ClO3-}$
Element+ite eg. $\ce{ClO2-}$
Hypo+element+ite eg. $\ce{ClO-}$
1-If I see an oxyanion ...
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Could you tell me the name of this compound please? [closed]
Could you please tell me make of this compound?
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What is the IUPAC name of an ether if two alkyl groups attached to oxygen atom have functional groups attached to them?
Here, both alkyl groups attatched to oxygen atom have ketone functional group attatched to oxygen. Then, how will I write the IUPAC name?
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Naming of this organic compound
I am unable to share the image, so sorry; but can you tell me which is the correct name from these 2 of the same compound.
3-(1-chloromethyl)-2-(1-methylethyl)-pentan-1-ol
or
4-chloro-3-ethyl-2-(1-...
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1
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173
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Comprehensive Functional-Group-Priority Table for IUPAC Nomenclature
I can't seem to find a source for a comprehensive list of FG-priorities. I also am not aware of any system to determine the priority for more uncommon FGs.
One of the two would be really helpful if ...
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Assigning configuration of chiral plane - selecting of the pilot atom
I am little confused about when it comes to assigning configuration of planarly chiral cyclophanes - and I think it comes down to selection of pilot atom.
All sources I have came across say that the ...
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2
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Difference between sodium aluminate and sodium metaaluminate
So I was studying Chemistry (Hydrogen - Uses, Properties and Preparation) from 2 different textbooks (based on Grade 9 syllabus, I.C.S.E. Board, India) and I found what seems an astounding anomaly to ...
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How to write formula for potassium hydrogenpyrophosphite?
I know that pyrophosphite by itself is $\ce {({P_2}{O_5})^{4-}}$. My question is about the hydrogen part- how to know how many hydrogens to add? The answer key for this question says the compound is $\...
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Standard suffixes for compounds?
Long ago, I learned that suffixes like -ide, -ate, -ose, etc. had specific meanings.
Now, I'm seeing all these drug ads on TV with generic names that all end in -ab or -ib. Do these have a standard ...
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Why is guanine sometimes referred to as "Acyclovir Impurity B"?
"Acyclovir Impurity B" is the name for guanine used by a handful of relatively low-traffic websites. Googling the term shows this. It is nearly always with a capital letter at the beginning ...
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1
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Difficulty in E-Z nomenclature and counting number of geometrical isomers
I have found above four molecules as the geometrical isomers just by drawing them and checking if they are superimposable. I'm not sure that these are the only ones.
I have tried using E and Z but ...
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Correct IUPAC name of 3 - chloro-1-phenylprop-1 -ene
In this molecule, what should I take the principal group as - the benzene or the propene chain?
I feel that we should take Benzene as the prinicipal ring and the name should be 3-chloropropen-1-yl ...
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In the nomenclature of Ethyl 2-methyl-5-oxocyclopentane-1-carboxylate, why is the ketone given a smaller Locant than the methyl group?
Ethyl 2-methyl-5-oxocyclopentane-1-carboxylate
The rules say that functional groups are given more priority than side chains but if there is more than one functional groups then we consult the ...
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1
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IUPAC naming of lysergic acid diethylamide (LSD) heterocyclic core and its locants
Wikipedia article about LSD says its IUPAC name is
(6aR,9R)-N,N-diethyl-7-methyl-4,6,6a,7,8,9-hexahydroindolo[4,3-fg]quinoline-9-carboxamide
which is quite complex. Especially its didehydroergoline ...
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Making Sense Out of The IUPAC Exo/Endo Definition
Am I missing something or is the IUPAC endo/exo definition completely illogical? The prefixes exo- and endo- in general (also in chemistry) mean away (outwards) and towards (into), respectively. The ...
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Why is 5-chloro-2-hexene numbered as such when it could be named 2-chloro-4-hexene and have smaller Locants?
We're learning IUPAC nomenclature of organic compounds and I came across this problem:
And it's IUPAC name is:
My question: Why did the numbering start from the left end when starting from the right ...
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1
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Why is it wrong to name 2-methyl-1-propanol (the preferred IUPAC name of isobutanol)1-methylpropanol?
Given the compound 2-methyl-1-propanol (isobutanol), the preferred IUPAC name is the aforementioned. But why is it wrong to name it 1-methylpropanol? Given that the methyl can't go to any other of the ...
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Is there a general single term for benzylic-like positions in non-benzene aromatic rings?
This is a simple vocabulary question. Is there a single chemical term in general use that generalizes the concept of "benzyl" to aromatic but not necessarily benzene rings?
For example, in ...
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Multi compartmental ODE's in chemical engineering
I am alien to the field of chemical engineering. And I am confused about equations, written by chemical engineers, including several variables belonging to different compartments.
Assume that,
$[X]$ ...
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Nomenclature of DIPEA
Why is Hünig's base called "N,N-Diisopropylethylamine" on Wikipedia, in the name DIPEA, as well as vendors like Sigma-Aldrich, rather than ""N,N-Ethyldiisopropylamine" (EDIPA)?...
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Does the ‘e’ from ‘-yne’ get dropped in compounds of higher functional groups?
What is the way of representing a triple bond in a compound of a higher functional group, like alcohol? Does the ‘e’ from ‘-yne’ get dropped like in the case of the ‘-ene’ suffix?
For example, would ...
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Element Names in English [closed]
Na - Sodium - Natrium
K - Potassium - Kalium
W - Tungsten - Wolfram
Sb - Antimony - Stibium
and so forth.
[English only] Why do we not use the names that match the symbols?
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Stereochemistry R,S configuration
I'm trying to find the R/S configuration of this molecule right here:
At first I tried to find the rotation and then reverse it (since H is pointing outwards), I got an S configuration (drawn poorly ...
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Are substituents placed alphabetically in the name of a cycloalkane?
I named this molecule 1,5-diethyl-2-methyl-4-propylcyclohexane. Is this correct? Or should we somehow use the size of the substituents?
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Why do we say "octadiene" and at the same time name another compound "octanediol"?
Why do we say "octadiene" and at the same time name another compound "octanediol"? We also say for instance "pentanedione", but on the other hand we say "butadiyne&...
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Does the ace- or acet- prefix denote simplest forms of functional groups? [duplicate]
For example Acetone has the shortest carbon chain in which a ketone functional group can be added. Other examples include Acetaldehyde, Acetylene. Was this some sort of older naming system in which ...
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3
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What is the overall oxidation number of polyatomic ions?
In a polyatomic ion, the sum of the oxidation numbers of all atoms is equal to the overall charge on the ion. However, does this polyatomic ion have an overall oxidation number?
We also know that the ...
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IUPAC Names for trihalomethanes
The drinking water section of the Massachusetts DEP mandates the electronic submission of analytical results. The compound Chlorodibromomethane must be entered when reporting just trihalomethanes and ...
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Is the 'i' prefix for "iso-" italicised?
I want to abbreviate pseudoisocytosine. Should it be "ΨiC" or "ΨiC"?
I would usually write "sec-butyl", "tert-butyl", etc, and using "t-BuOH" for &...
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1
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Priority of Alphabetic order vs Lowest locant
I am confused about usage priority of lowest locant and alphabetical order rule(s)
For example :
3-ethyl 4,4 - dimethyl hexane
4-ethyl 3,3- dimethyl hexane
Which is considered correct (or preferred) ...
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Why is active sec-pentyl group called so?
My teacher as well as Wikipedia — Pentyl group use the following names for the “pentyl” groups:
Group name
Structure with attachment point
1
active sec-pentyl
2
sec-pentyl
3
active pentyl
If a ...
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2
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With respect to nomenclature, when is parent chain length a bigger priority than having functional groups before double bonds?
I came across this problem in Organic Chemistry as a Second Language. In the book, it is taught that one must prioritize functional groups over double bonds, while also trying to keep both as low in ...
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Manganate and Permanganate
In my chemistry course, the addition of the “per” prefix generally means that the oxoanion of relevance will have one more oxygen than the “base” ion.
e.g. chlorate = $\ce{ClO3-}$, perchlorate = $\ce{...
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Purpose of "1H" in naming of substituted heterocyclic compouns [duplicate]
I had a curious thought about the following molecule's name:
For such a simple molecule it seemed awfully complicated. From what I gathered, the "[c][1,2]oxaborinin-1-ol" stems from the ...
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IUPAC name for dicarboxylic acid with aldehyde and amine groups
The IUPAC name of the structure is:
(A) 3-amino-2-formyl butane-1, 4-dioic. Acid
(B) 3-amino-2, 3-dicarboxy propanal
(C) 2-amino-3-formyl butane-1, 4-dioic acid.
(D) 1-amino-2-formyl succinic acid
...
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Which is correct - molybdate or molybdenate?
Most websites (including Wikipedia) say that the anion MoO42- is called a molybdate ion, although some websites use molybdenate instead. Which one is correct, and if one of them is correct, is the ...
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Does methyl or aldehyde group have higher priority when choosing the main chain of carbonyl compound?
As far as I know, both following names seem to be correct for the compound below. Please explain which IUPAC name is correct by which IUPAC rules:
4-formylpentanoic acid (methyl group counted in the ...
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