Week 1 Chapter 12 Flashcards
The most common structural piece in organic chemistry is the carbon-carbon bond. Most organic compounds are filled w/ these.
* Other peices that attach to these chains are called what?
Functional groups
Compounds that contain only carbon and hydrogen, and that contain no double or tripple bonds? They are the simplist kinds of organic compounds
Alkanes
* We can think of many other organic compounds as being built from an alkane framework
* Like the frame of a house, with other peices arranged around the molecule
Below are a few exmaples
* Notice they are made only of carbon and hydrogen
* Alkanes are organic compounds that contain only carbon and hydrogen and have only single bonds
* These structures form the basic frameowrk of organic molecules
Specific alkanes are given the suffix
* if they have this suffix what does it mean?
Ane
* If they have this suffix, that means they contain only single bonds, no double or tripple bonds
* A compound that contains no double or tripple bonds is sometimes called saturated
Another name for alkanes is paraffincic hydrocarbons. What does this mean?
Saturated hydrocarbons –> because alkanes only have single bonds meaning they’re fully saturated
The prefix in the alkanes name also tells us how many carbons are connected to the chain.
* So it will contain meth, eth, prop, but, pent, hex, hept, oct, non, or dec and will be followed by ane if it only contains those single bonds.
What is the name of this alkane ?
Pentane
* each of those carbon bonds is fully saturated (we assume the hydrogens are on there), meaning there are only single bonds in the sturcture
* We count the carbons and see that there are 5 = pent
A chain of carbons in an alkane is called a _ chain
Alkyl chain
Sometimes there are smaller alkyl chains attached to the main chain of an alkane. The same prefixes can be used to tell us how many carbons are in these smaller branches
Numbers are used to count how far along the chain these branches occur. You need to start on the end of the chain and count the carbons until you get to the place where the branch occurs. If there are two different possible chains, choose the longest chain as the base name. If there are two different directions possible, start at the the one that gives the lowest number of for the branches
* meaning if counting from right –> left yields smaller carbons for these chains do that (the ones branching off)
If there are two different branches of the same size on a chain, you need to say so. A different prefix is used to say how many of the same piece are present
* basically if 2 groups branch off the same carbon you need to say so
What is a hydrocarbon molecule?
Molecule consisting only of carbon and hydrogen
KNOW: Alkanes are fully saturated –> meaning they have the maximum # of hydrogens possible –> no double or tripple bonds
* any alkane has the suffix “ane”
* The prefix is determined by how many carbon atoms are in the molecule
Name this hydrocarbon (alkane)
Start by naming the longest chain of carbons in the molecule
* = butane
* added the suffix ane because its an alkane (meaning theres only single bonds and its only carbon/hydrogen)
Next number the hydrocarbon in the direction that makes the substituent be on the lowest # for carbon. In this case it would be on carbon 2 (numbered from left to right because it yielded a lower # carbon)
* note if we named from right to left the substituent would’ve been on carbon 3
So the substituent is made of 1 carbon (you don’t count the carbon thats already in the main group). Meaning we use the prefix Methyl
* again this is a substituent coming off of the main chain
* so were going to call this a methyl group (if it was 2 carbon we would call it an ethyl group)
So we only have 1 substituent so this is fairly easy to name
* start by stating the location of the subsitutent (the carbon its on)
* Then state how big the substituent is (in this case its 1 = methyl)
* Then add the name of the alkane (hydrocarbon) = butane
2-Methylbutane
What is a substituent
is any atom or group of atoms that replaces a hydrogen atom on a parent structure (usually a hydrocarbon backbone).
It would be the vertical line in the picture below. Its the thing thats replacing where the hydrogen would’ve been on carbon 2.
Name the alkane below
Start by finding the longest carbon chain
* In this case its in the horizontal plane (may not always be this way)
Next number it, but make sure the substituents have the lowest number possible
* In this case we number R to left because a substitent occurs on the second to last one and near the middle
* Numbering this way we get the numbers 2,5
* If we numbered the other way we would get the numbers 3 and 6, which are higher. So we dont do it left to right
So we find that the alkane has 7 carbons = heptane
Subsitutent on carbon 2 = methyl (made up of 1 carbon)
Subsituent on carbon 5 = ethyl (made up of 2 carbons)
Now to further name this, we need to list the subsituents in alphabetical order in this case ethyl comes before methyl
5-ethyl-2-methylheptane
* NOTE: inbetween all words and #’s we have a -
* NOTE: Inbetween words there is a ,
Name this
Now, if we have a subsituent occuring at the same position, regardless of if we number from the left or the right we are going to give priority to the substiuent the occurs first alphabetically.
In this case we have a methyl and an ethyl occuring on carbon 3, regardless of if we start from the left or the right. However E comes before M so we start on the right to make the ethyl one have the lower number
3-ethyl-4,5-dimethylheptane
* so basically the ethyl part makes sense because its an ethyl on carbon 3
* theres a single methyl on both carbon 4 and carbon 5, so we state both of those
* then we let the reader know that there are 2 methyls by putting dimethyl before hepatne
* NOTE: The di portion is not taken into acount when asessing alphabetical order –> you must still e before m
Name this alkane
hardest part is knowing to change the direction
what are Aliphatic hydrocarbons?
what are Alicyclic hydrocarbons?
Branched chains of hydrocarbons
ring of saturated hydrocarbons
* cyclo = carbons wrap in a ring
name this hydrocarbon?
Well its still an alkane because its only made of hydrogen, carbon and single bonds
* however it grabs the prefix cyclo because its a carbon ring
Cyclopentane
* pentane = 5 carbon alkane
All of these get the prefix cyclo –> basically get this prefix when the carbons connect to eachother (can be as small as a triangle)
These are still alkanes, so all the other rules are the same
Name this hydrocarbon
Same rules, except don’t have to indicate the carbon its on because theres only one substituent. We could simply rotate it can get it whereever, so dont have to name the carbon when theres only one substituent
MethylCyclohexane
* always start with the substituent (like before)
* then add cyclo when theres a ring (can be as few as 3 forming a triangle)
