Basic IUPAC Organic Nomenclature

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Haloalkanes

(a halogen tacked onto a carbon) Alkanes with one or more hydrogen atoms replaced by halogen atoms. As substituents, they're "halo-" (chloro, fluoro, iodo). As alkanes though, they're halides. There are two ways to name these: Haloalkane style: the root name is based on the longest chain containing the halogen (bc the halogen is part of the parent chain). The chain is numbered to give the halogen the lowest locant possible and the suffix is "ane" (eg. bromoethane) Alkyl Halide style: two parts: the first one is how many carbons the molecule has and the second part is the name of the halogen on it with "ide" at the end. (eg. ethyl bromide)

Sulfides (Thioethers)

(pretty symmetrical one that is sulfur between two chains. O and S are like siblings). Compounds that consist of one or more elements combined with sulfur (insoluble??). Naming takes the form of "alkyl alkyl sulfide" when it's the highest-priority group, or "alkylthio-" when it isn't. They're named pretty much the same way as ethers except replacing "-oxy-" and "oxa-" with "-thio-"

List the root names of the parent chain (prefixes) depending on how many carbons it has

1 - meth 2 - eth 3 - prop 4 - but 5 - pent 6 - hex 7 - hept 8 - oct 9 - non 10 - dec 11 - undec 12 - dodec 16 - hexadec 18 - octadec 20 - icos

List the order of priority of functional groups you know

1. Carboxylic acids 2. Acid anhydrides 3. Esters 4. Acyl halides 5. Amides 6. Nitriles 7. Aldehydes 8. Ketones 9. Alcohols 10. Thiols 11. Amines 12. Ethers 13. Sulfides 14. Alkenes (double bonds) 15. Alkynes (triple bonds. Yes, I triple-checked. They are of lower priority than alkenes) 16. Alkyl Halides 17. Nitro 18. Alkanes (single-bonded chains like methyl and ethyl)

First Point of Difference Rule

1. Functional group gets the lowest locant 2. If there is a "tie" (if there are two substituents attached to the same carbon), then the numbering is decided such that the lowest locant is repeated (for example, if you have a methyl and an ethyl group on the same carbon, you'd try to make it so that the repeated number is as low as possible) 3. If there's no first point of difference, alphabetical order will save your life. 4. Omit numbering only if the group is on the first carbon (like butanol) or if its placement is completely unambiguous (methanol)

What are the different ways to modify names of organic compounds to indicate the functional groups present?

1. Substitutive: the highest priority functional group modifies the suffix of the root name, while all other groups (substituents) change the prefix of the root name (eg. what you learned in high school. 1-fluoro-3-methylcyclobutane) 2. Functional group: names the compound based on the highest priority functional group (eg. alkyl halide, ether, alcohol, ketone, etc.) 3. Replacement: used to indicate when a carbon is replaced by another atom 4. Conjunctive: combines named subunits (eg. cyclobutanoic acid) 5. Common/trivial: due to common use, simpler names have been adopted by IUPAC (eg. acetic acid is commonly referred to as vinegar)

Describe naming for fused and bridged bicycloalkanes

1. The root name (at the end) is defined by the number of carbons on the entire molecule EXCLUDING THE BRIDGEHEAD ATOMS. Numbering starts at a bridgehead atom and goes around the molecule via THE LARGEST RING (this one makes a shape instead of an 8). This takes priority over alkyl group numbering, so unless the alkyl group is on a bridgehead, its locant is something other than 1. 2. It follows the format "bicyclo[x.y.z](root name)" where x is the number of carbons in the biggest ring excluding the bridgehead atoms, y is the number of carbons in the smallest ring excluding the bridgehead atoms, and z is the number of carbons shared between the two rings excluding the bridgehead atoms (this one applies to bridged bicycloalkanes more than fused. the z value for fused bicycloalkanes is 0) 3. Any substituents' names (as normal) go before the "bicyclo{x.y.z]". The substituent's carbon atoms aren't counted in the name of the parent chain.

Describe how to name diamines and polyamines

1. The root name is based on the longest chain that contains ALL amine groups and numbering is given such that ONE of the amine groups contains the lowest locant possible. 2. The appropriate prefix (di, tri, etc. to indicate how many amine groups there are) and notation of their locants in the name is the same as you would with an alke/yne. 3. You're still following the regular naming rules of amines so you get a name that looks like "1,2-ethyldiamine" or "ethyl-1,2-diamine" 4. When more than one of the amines is substituted (AKA: is a secondary or tertiary amine), add the "N" as N and N' and N" to distinguish them. 5. When only one of the amines is substituted, you get a funky-looking name like "N-ethyl-1,3-propyldiamine" because you don't have to specify which amine the ethyl branch is on.

List the exceptions to the alphabetical order rule for naming alkyl groups

1. When naming something like tert-butyl, this still goes by the "b", not by "t".

Bridged Ring System

A bicyclic ring system in which the two rings share non-adjacent carbon atoms. Like if the two carbons of a fused ring system had a third carbon joining them from a different plane. To which ring does the molecule belong? Both. Both is good.

Ester

A family of organic compounds characterized by the presence of a carbonyl group bonded to an oxygen (it's essentially a carboxyl group but the hydrogen atom has been replaced with a full other hydrocarbon) AKA the lovechild of a carboxylic acid and an alcohol (huh, opposites do attract) Two parts for names: 1. Take the alcohol and replace "anol" with "yl" (eg. ethanol to ethyl) 2. Take the carboxylic acid and replace "oic acid" with "oate" (eg. methanoic acid to methanoate). The alcohol goes first and the carboxylic acid goes second (eg. ethyl methanoate) If there are branches on either group, the branches are named at the beginning of their respective section (eg. 2-methylpropyl 3-butanoate)

Nitro

A nitrogen with a formal charge double-bonded to an oxygen and single-bonded to another oxygen with a formal charge. This is a resonance diagram. The double bond can be on either one of the oxygens. Each of the oxygens can have either the double bond or the formal charge but not both.

Enyne

A title for a molecule that indicates the presence of both an alkene and an alkyne. It's a freaking ship name. These are named just like alkenes and alkynes and polye/ynes, just that it ends up naming both the alkene and the alkyne (in that order), so it looks something like (prefix)-(alkene locant)-en-(alkyne locant)-yne

Substituent

An atom or group of atoms that can take the place of a hydrogen atom on a parent hydrocarbon molecule (anything that isn't the principal functional group is a substituent)

How do you determine the root name of an organic compound?

By looking at the longest chain of carbons and going from there (modifying the name)

Benzene

Consists of a ring of six carbon atoms with alternating single and double carbon-carbon bonds. Since benzene and its relatives have their own reactions, they're categorized as arenes. The way to name these is just to shove "benzene" at the end of the name (there's no root name or anything. It's just prefix-benzene). For example: "bromobenzene" for alkyl halides, "ethoxyenzene" for ethers, "nitrobenzene" for nitro groups.

Mr. Oborn's triangular/train guide to drawing esters

Draw a triangle around the COO group so that the C is the base of the right angle of the triangle. The triangle will be pointing to the alcohol while the carboxylic acid will be bonded to the carbon forming the right angle of the triangle.

Cis and Trans Isomers

For these isomers to be possible, one substituent on one end of a C=C bond must the identical to ONE OTHER substituent on THE OTHER end of the C=C bond. Naming of "cis" and "trans" goes before everything else (bc it's the same molecule name, just with different stereochemistry so the "cis" or "trans" is tacked onto the beginning of the name)

Alkenes

Hydrocarbons that have a double bond BETWEEN CARBONS. These are unsaturated compounds. General formula is C(n)H(2n) The first three (methene, ethene, and propene) are gaseous and the rest are liquid. The boiling point of these is LOWER than that of an alkane with the same number of carbons because the shape isn't altered, and alkenes will have less things sticking off of it. Numbering starts from the end of the parent chain closest to the double bond. If a cyclic molecule, then you start at the double bond and continue numbering through the double bond. Names go by numbering the double bond like so: but-2-ene. When they're substituents, they become "alkenyl" groups, and when there's more than one of them you number the double bonds like you would with other substituents and add the prefix to the end (eg. diene if it's 2 double bonds, triene if it's 3 double bonds, etc., just remember to put "metha, etha, propa, buta..." instead of "meth, eth, prop, but...").

What does numbering look like on an enyne?

I think they're tied? As far as I know, you go with whichever numbering gives you the lowest locants.

In what order are the prefixes of substituents added to the root name?

In alphabetical order regardless of its locant

Locant

In nomenclature, a number (and occasionally letter) used to identify the location of a substituent or the principal functional group. Starting from the end of the longest continuous chain that gives the principal functional group the lowest number possible.

Here's a fun fact in case you need a break!

Ketones are formed in the body during uncontrolled diabetes or in starvation. Given this, it shouldn't bring me so much joy to look at its symmetrical structure.

You definitely have to know this, so here are some common names for substituted benzene

Methylbenzene = toluene Ethenylbenzene = styrene Phenol = benzene as an alcohol Methoxybenzene = anisole Aminobenzene = Aniline Benzoic acid = benzene with a COOH Benzaldehyde = benzene with a COH Benzonitrile = benzene with a CN

Polycyclic Alkanes

Molecules that have more than one ring. These systems can include substituted, spiro ring, fused ring and bridge ring systems. The simplest of these systems are when they're a system of two cyclopropane rings arranged in different ways.

E/Z naming (the Cahn-Ingold-Prelog Priority Rules)

NOT THE SAME AS CIS/TRANS!!! This one is based more on priority. First off, imagine each alkene as two pieces, each containing one of the carbons from the double bond (like you took a katana and cut the double bond in half). 1. Assign priority level (high = 1, low= 2) to each atom on your half-molecule based on atomic number (if there are isotopes, D > H). Higher atomic numbers have higher priority. 2. Looking at the molecule as a whole again, if the higher priority branches are on the same side, then the molecule is a Z alkene (zusammen = together in German). If they're on opposite sides of the molecule, it's an E alkene (entgegen = opposite in German) NOTE: E doesn't always mean trans and Z doesn't always mean cis. NOTE: tack on the E or Z at the beginning of the name of the molecule in brackets separated from the rest of the name by a dash as well. NOTE: multiple bonds don't matter when assigning priority level to the groups on either side of the alkene.

Alkyne

Naming legit works the same way as with an alkene, just that when it's a branch, it's an "alkynyl" group. For a polyyne, the root name is based off the chain that contains both ends of all triple bonds. Additionally, add the "a" in front of the prefix.

Aldehyde

R - CHO the ones that look like esters but instead of COO it's COH The root name is based on the longest carbon chain containing the carbonyl. Because it's always going to be at the end of the molecule, you don't have to worry about locants. You have two options for this one: 1. Replace the "ne" at the end with "nal" 2. Add the prefix "oxo-" to the beginning of the root name.

Nitriles

R-C---N. RCN, triple bond between the carbon and the nitrogen. The R group is the side chick. To name: When it's the principal functional group, the name of the molecule is "alkyl cyanide" OR "alkane nitrile" or "alkanonitrile". When it's not, the prefix "cyano-" gets tacked onto the start of the root name (like with haloalkanes). NOTE: there is only a space if the nitrile is the principal functional group. If not, then "nitrile" is just tacked onto the end without taking any "e"s off or anything.

Ethers

R-O-R' (**makes chickenosaurus sound**) (another pretty symmetrical one that is oxygen between two chains). Naming works like this: For simple ethers: alkyl alkyl ether. You name the R group on either side of the oxygen in alphabetical order if they're less complex than the ether itself. If it's the same R group, then it's "dialkyl ether". For intermediate ethers (when one of the R groups is more complex/higher priority than an ether): the less complex group and the oxygen become an alkoxy branch (named "prefix-oxy") and the more complicated R group defines the root name. The prefix on the alkoxy branch is defined by the number of carbons on the less complicated (remember to add the locant). So you end up with something like "1-methoxybutene" or "1-methoxyethene". To show the chemical formula for these, put the "OCH3(CH3)" in brackets. For complex ethers (when both R groups are more complex than the ether): the oxygen alone becomes the substituent and "oxa" is placed before the root name, which is defined by the longest continuous chain INCLUDING THE OXYGEN, so something with four carbons and an oxygen in between them would be named "(locant)-oxaPENTene". Note that when naming, you're still trying to end up with the lowest locants possible, so when the ether becomes a substituent, lowest locants takes priority over the ether.

Alcohols

R-OH (anything with OH as the highest-priority group) Substituent name is "hydroxy" and goes before the root name of the molecule. If it's the highest-priority functional group, the name is "-ol" at the end of the root name, which replaces the "e" in alkane/ene/yne. When there is more than one, you name it the same way you would an alkene so the name ends up looking like "pentan-1,2-diol"

Multiplier

The "di", "tri", or "tetra" prefix that indicates how many of a specific substituent there are.

Carboxylic Acid

The **makes pigeon sound** COOH group To name these, just replace the "ane" with "anoic acid". If this isn't the highest-priority group, then it's a "carboxy" branch and becomes subject to alphabetical order and locants.

How do you deal with E and Z naming if there's more than one double bond?

The E or Z stays in the same place as it would, but then you tack on a number before the E or Z to specify its locant (eg. (2Z,4E)... represents an E alkene located on C4 of the total molecule and a Z alkene located on C2 of a molecule. Numerical order is followed, not alphabetical.). These same rules apply for the cis/trans naming system.

Ketone

The beautifully symmetrical carbonyl smack dab in the middle of two functional groups. Naming looks a lot like with ethers: When it's the principal functional group: alkyl alkyl ketone When it's not: suffix "-one" or prefix "oxo-" Assignment of locants works the name way as with alkenes and amines. pentan-2-one or 2-oxopentane or 2-pentanone.

Acyl Halide

The carboxylic acid derivatives that look like esters but instead of COO it's COX where 'X' is a halogen. To name: 1. the root name is based on the longest chain containing the functional group. Since these will be at the end of the chain, you don't have to worry about locants. 2. When it's the principal functional group, it's named "(acid name) acyl" OR "(acid name) halide". When it's not, it gets the substituent suffix "oyl halide", specifying the halide (eg. propanoyl bromide)

Principal Functional Group

The highest-priority functional group used to define to which category the compound belongs. This is usually given the lowest locant possible.

Amides

The product formed in a reaction between a carboxylic acid and an amine. The ones that look like esters but instead of COO it's CON and the N is attached to two other chains. To name: 1. The root name is based on the longest chain that contains the amide group. 2. If the amide nitrogen is substituted (if the N on the amide gets R groups to replace the hydrogens), name it as you would an amine, using "N" as the locant for these substituents. 3. When it's the principal functional group, the name of the molecule follows the format "alkyl alkanamide". When it isn't, tack on "amide" as the suffix of the name.

Alkanes

The simplest hydrocarbons that contain single covalent bonds, in their barest form between carbons and hydrogens. AKA saturated hydrocarbons. Naming goes locant - substituent prefix - root name General formula is C(n)H(2n+2) Substituent name (AKA its name when it's a branch): (prefix)-yl Simple cylic alkanes are named by adding "cyclo" to its chain name.

Acid Anhydrides

The symmetrical R - COOOC - R group As a derivative of the carboxylic acid, this is named "alkanoic anhydride" if it's the principal functional group, and if it's not, it's still named "-oic anhydride". I don't know what the difference is yet. Stand by. Cyclic anhydrides are named "-dioic anhydride" Symmetrical anhydrides (ones that have the same stuff on either side of the anhydride) are named "alkanoic anhydride" Asymmetrical anhydrides (resembling esters) are named by doing the same thing as symmetrical anhydrides except you list the alkanoic groups.

Disubstituted Benzene

There's a special way to name this. Two ways: 1. Use the locants as usual 2. Name the combinations (this is only for benzene systems). If the two groups are on opposite ends of the benzene molecule, the prefix "para" is added to the name. The picture describes the rest. Just look at it (as you can see this is where I'm starting to get anxious to finish). NOTE: the "ortho", "meta", and "para" are treated just like any other locant. Additionally you can just go "o-", "m-", or "p-" NOTE: when benzene has more than two things sticking off of it, it's customary to use some of the more common names for certain benzene substituents (eg. 2-bromo-4-chlorotoluene)

Describe naming for cycloalkanes

They're either cycloalkyl substituted alkanes or alkyl substituted cycloalkanes in that they're either treated as branches when they're smaller than the parent chain or treated as the parent chain with a freakish chain attached to it. If it only has one thing on it, no locants are necessary. If the ring is a branch, then the name looks something like "#-cyclo(prefix')yl(prefix)ane". If it's the parent chain, then it becomes something like "(prefix)ylcyclo(prefix)ane"

What happens when benzene is a substituent?

This is to indicate the presence of C6H5. For this, it's a phenyl branch. On top of that, don't confuse phenyl with benzyl (C6H5CH2). You can differentiate these two because benzyl has an extra carbon on it (like phenyl is a balloon on its own and benzyl is a balloon with a string)

Substituted System (polycyclic alkanes)

When the rings are on different parts of the molecule such that they share no common atoms.

Spiro Ring System

When the rings share a single atom in common (think the center of a bow being the atom shared by two cyclopropane molecules). To name: 1. the root name is based on the number of carbon atoms in the parent chain and the carbons are numbered starting from the carbon next to the spirocenter on the smallest ring, and then continues like you're drawing the number 8 around the smaller ring, crossing through the spirocenter and around the bigger ring (if this doesn't resolve the numbering, proceed as with any other carbon chain). 2. It follows the format "spiro[x.y](prefix for number of carbons in the whole molecule)ane" where x is the number of carbons on the smaller ring and y is the number of carbons on the bigger ring. This is EXCLUDING THE CARBON THEY SHARE. 3. Any substituents' names (as normal) go before the "spiro{x.y]". The substituent's carbon atoms aren't counted in the name of the parent chain. The carbon they are on becomes C1.

When can an alkene exist as a stereoisomer (geometric isomer)?

When they have two different substituents at EACH end of the C=C bond.

R/S Naming (Chirality)

When you have a molecule with a chiral center, this is also something you need to name so this is how you do it: 1. Look at the four things attached to the central carbon 2. Assign priority to them based on atomic number just like with E/Z 3. Take the lowest priority group and imagine it facing away from you (so you have a triangle of the other three groups facing you) 4. Rank these in priority. If this priority is clockwise, then it's named as an R stereoisomer (rectus = right handed in Latin). If it's counterclockwise, then it's named as an S stereoisomer (sinister = left handed in Latin) 5. If there is more than one stereocenter (chiral center) on the molecule, then you put a locant on the R/S like so: 2R or 4S. Alphabetical order will save you when listing these.

When choosing a parent chain, what happens if you have two chains that are equally long?

You choose the one that has the simplest substituents (not the simplest chain, the simplest substituents. The chain can be perfectly straight but if it's got an isobutyl when the alternative was two methyl branches and a messed up parent chain, you done goofed).

How do you name an alkene when it's a substituent?

You literally take its name and instead of ending the name in "ene" you end it with "enyl". And that's it ;)

Describe how to deal with complex alkane substituents

You need to treat it as its own molecule: 1. Find the point at which the substituent attaches to the rest of the molecule 2. The carbon that attaches the substituent to the parent chain (but is itself part of the substituent) is the C1 of the substituent. 3. From C1, determine the longest continuous chain of the substituent. 4. Identify any substituents coming off of the parent chain 5. Name it and assign locants as you would any other molecule To integrate it into the name of the entire molecule: 1. the complex substituent's name appears in brackets proceeded by its locant on the total molecule 2. The complex substituent is alphabetized in the total molecule name based on the first letter of its name, like any other substituent. The bracket isn't separated from the total name by anything. It's just tacked on like the bracket is made of velcro. REMEMBER THAT NUMBERS ARE SEPARATED BY COMMAS AND NUMBERS AND LETTERS ARE SEPARATED BY DASHES.

List some common basic alkane substituent names

You've got your methyl, ethyl, propyl and such, but then we get into stuff like tert-butyl or iso-propyl and that just refers to a branch that appears to have branches sticking off of it. For example: tert-butyl looks like a full-fledged tetrahedral molecule and the middle carbon attaches to the rest of the molecule. iso talks about an alkane that splits into two even branches. Isopropane looks like a 'Y' and isobutyl looks like a 'Y' with a longer stem. sec-butyl is additionally one that looks like a 'Y', but instead of splitting into even branches, the 'Y' shape ends up looking kind of lopsided as the stem is short and one of the branches is longer than the other.

Fused Ring System

a molecule in which two or more rings share two adjacent carbon atoms (like adenine and cytosine, or two cyclopropanes joined together to make a rhombus)

Epoxides

cyclic ethers -more reactive due to strain -react with water in presence of acid catalyst to form diols These are funky because they're treated like alkenes. That oxygen is treated like a double bond when it comes to naming. When they're the highest priority group, they're named "(alkene) oxide", and when they're a substituent, it looks like "(locants)-epoxy-(root name)". Alkene Oxide: named after the alkene below it (think of it like the O is a thumb tack on which the alkene is hanging to a wall). The name of the alkene and then "oxide" tacked on to it is how these are named. (eg. 1-butene oxide). ONLY ONE CARBON WITH THE LOWEST LOCANT NEEDS TO BE NUMBERED. Epoxy-style: the root name is based on the longest carbon chain containing the epoxide (both C-O bonds) and the chain is numbered to give the epoxide the lowest locant possible. EPOXY STYLE DOESN'T USE "-ene", it uses "ane" for the root name. (eg. 1,2-epoxybutane). BOTH CARBONS NEED TO BE NUMBERED NOTE: the term "oxirane" is also used to describe epoxides. NOTE: both carbons on the epoxide count towards the root name carbon count. NOTE: when an epoxy is on a cyclic molecule, it doesn't get locants. NOTE: these are subject to the rules of alphabetization in terms of naming too.

Provide the complex and common name for the common alkane substituents

isopropyl = 1-methylethyl sec-butyl/s-butyl = 1-methylpropyl isobutyl = 2-methylpropyl tert-butyl = 1,2-dimethylethyl Note that isobutyl and sec-butyl look the same on their own, just that they're attached to the whole molecule by different ends of the 'Y'.

Thiols

organic compounds containing sulfahydryl groups (R-SH). The ones that look like alcohols but instead of OH it's SH. One is surprised and the other wants quiet. Treat these like alcohols when naming (maintaining its priority). If it's the principal functional group, the root name has the suffix changed to "-thiol". If it's a substituent, "sulfanyl" is tacked onto the prefix of the root name (with respective locants). Note that the only way these names differ from alcohols is that the "thiol" doesn't replace the "e", instead tacking it on at the end of the root name so it looks like "butane-1-thiol".

Amines

organic compounds with an amino group. There is a variety of naming schemes: When they're the principal functional group: alkylamine OR alkanamine. When they're not: -amine OR amino-. the root name is based on the longest chain containing the amine and numbered such that the amine has the lowest locant possible: 1. Primary Amines (R-NH2): Add "amine" at the end of the "alkyl" or "alkana" root name. It's a suffix! 2. Secondary Amines (R2-NH): the shorter chain attached to the NH is treated as a substituent with the letter "N" as the locant. The "N" is listed before the other locants. Add "amine" at the end of the "alkyl" or "alkana" root name. 3. Tertiary Amines: The difference between this and the others is that there's an extra "N" so the name ends up looking like "N,N-dimethylmethylamine" (AKA trimethylamine) or "N-ethyl-N-methylcyclohexylamine". NOTE: "N" is just another locant. Treat it the same as numbered locants (except that this goes first)


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