Organic Chemistry

What is organic chemistry?  Organic chem is the study of compounds that contain carbon  Remember, carbon can form 4 bonds  Because of this, there needed to be a specific naming system for all of these different compounds, as defined by the IUPAC naming system

When drawing…  When drawing the structures for organic compounds, you will often not see any carbons or hydrogens present, but instead a bunch of lines.  Each point on the line represents a carbon, and we fill in the extra bonds with hydrogens

Hydrocarbons: contain only C and H  The simplest form are known as alkanes  Their general formula is C n H 2n+2  When naming, use prefixes to show how many carbons are present, followed by –ane  C 2 H 6 =ethane  When these chains have groups stemming off a carbon, we number the carbons, so we know which one the group comes off of

Naming Alkanes 1. Find longest chain (can zig zag). Color or draw a line through it. a. Name using 1 st worksheet – this is last name. ex: C-C-C-C-C-C = Hexane 2. Color any sides groups (different color) or circle side groups. a. Count from both ends to determine shortest number to a side group. b. Number main chain C’s c. Locate side group and name using prefixes but change ending to -yl

Example 1. Longest chain is 8 C’s = Octane (last name) 2. Shortest numbering is from RIGHT C. 3. B. there are 3 side groups working from the right. 3- ethyl, 4-propyl, 5-propyl Final Name: 3-ethyl, 4-propyl, 5-propyl octane

Alternate name  3-ethyl, 4,5-dipropyl, octane 7

Double and triple bond hydrocarbons  When there is a double bond present between Carbons (need at least 2), we call those alkenes  When only 1 double bond is present, the general formula is C n H 2n  Use the same naming style as alkanes, but ends in –ene  Ex: Butene  When a triple bond is present between carbons, we call those alkynes  When only 1 triple bond is present, the general formula is C n H 2n-2  Use the same naming style as alkanes and alkenes, but ends in –yne  Ex: butyne  For these, number the carbon where the double or triple bond occurs

Number of carbon atoms AlkaneAlkane (single bond) AlkeneAlkene (double bond) AlkyneAlkyne (triple bond) 1Methane-- 2EthaneEthene Ethyne 3PropanePropene Propyne 4ButaneButene Butyne 5PentanePentenePentyne 6HexaneHexeneHexyne 7HeptaneHepteneHeptyne 8OctaneOcteneOctyne 9NonaneNoneneNonyne 10DecaneDeceneDecyne

Aldehydes and ketones  Aldehydes and ketones are organic compounds which incorporate a the functional group C=O.  The carbon atom of this group has two remaining bonds that may be occupied by hydrogen or other substituents.  If at least one of these substituents is hydrogen, the compound is an aldehyde.  If neither is hydrogen, the compound is a ketone.

 When naming, use the prefixes used for alkanes, but the suffixes are:  -al to aldehydes and -one to ketones  Since an aldehyde carbonyl group must always lie at the end of a carbon chain, it is by default position #1, and therefore defines the numbering direction.  A ketone carbonyl function may be located anywhere within a chain or ring, and its position is given by a locator number.  Chain numbering normally starts from the end nearest the carbonyl group

Alcohols  Chemical compounds with an –OH attached to one of the carbon groups  Alcohols are usually named by the first procedure and are designated by an -ol suffix, as in ethanol, CH 3 CH 2 OH  May also see it as ethyl alcohol

Ethers and esters  Ethers are two simple hydrocarbon chains that are separated by an oxygen.  Esters are the same except they have a double bonded oxygen on the carbon adjacent to the oxygen separating the two hydrocarbon groups.

Carboxylic acid  The general formula of a carboxylic acid is R−C(O)OH with R referring to the rest of the (possibly quite large) molecule.  The (O) is double bonded to the carbon

ACIDS  ANOIC ACID-ending -recognize by fishtail: end of molecule is O and OH (carboxylic acid – COOH) 1. Name chain with fishtail with ending 2. Name any side chains as Alkane OH I C-C-C-C-C=O