ORGANIC CHEMISTRY The scientific study of the structure, properties, composition, reactions, and preparation (by synthesis or by other means) of chemical compounds consisting of primarily carbon and hydrogen, which may contain any number of other elements, including nitrogen, oxygen, halogens as well as phosphorus and sulfur. ~Wikipedia

What is Organic Chemistry? Chemistry of the compounds of carbon- with a few exceptions (CO, CO2, carbonates, hydrogen carbonates cyanide and HCN) Many derived from living things and involved in life processes. About 8 million organic compounds known, but more than 3,500 new organic compounds are being reported every week.

Functional Groups Determine the reactivity of organic compounds An atom or group of atoms which is characteristic of a class of organic compounds and which determines the properties of the class. Important in classifying or systemizing organic compounds Main Types of Functional Groups Hydrocarbons Polar Single Bonds Carbon-Oxygen Double Bonds

Hydrocarbon Functional Groups Compounds which contain only carbon and hydrogen Three Main Types Aliphatic- Most hydrocarbons Alicyclic-Aliphatic compound which contains rings consisting of only carbon and hydrogen. Aromatic-Benzene like in character and properties

Aliphatic Hydrocarbons Alkanes Characterized by having only single bonds Alkenes Characterized by having a carbon-carbon double bond Alkynes Characterized by having a carbon-carbon triple bond See page 1055 for examples

Alkanes Serve as a backbone for functional groups Nonpolar so are soluble in other nonpolar solutions Saturated compounds because they have full number of hydrogens Boiling point increase with number of carbons Straight and Branching chains Straight chains All names end in “ane” with prefix according to number of carbons (meth-1, eth-2, prop-3, but-4, pent-5, hex-6, hept-7, oct-8, non-9, dec-10) To write molecular formulas, use CnH2n+2 To draw structural formulas, write the symbol for carbon as many times as necessary and then fill in with hydrogens. See page 1056 Table 25.1 Practice Problems #75 and 76 pg 74.

Branched Chain Alkyl group substituents, added to straight chain (use same prefix for number of carbons) Follow IUPAC rules for naming Find the longest chain of carbons in the molecule this will be the parent chain and end in “ane” Number the carbons in the parent chain, starting at the end where the most branches are. Determine substituents names and add numbers for where they appear on the parent chain. Use prefixes to indicate the appearance of a group more than once in the structure. For drawing structures draw carbons first then add hydrogens. Sample Exercise 25.1 & 25.2 pg 1059-1060 Practice problems #6, 21 and 22

Alkenes Hydrocarbons containing carbon-carbon double covalent bonds Unsaturated compounds because they don’t have full number of hydrogens To name alkenes by IUPAC system Find longest chain that has double bond in it, use prefix from alkanes but add “ene” instead of “ane” Start numbering the parent chain from the end where the end that makes the double bond have the lowest number. Follow other rules for alkanes but add a number at beginning of parent name to show where double bond is.

Alkynes Hydrocarbons containing carbon-carbon triple covalent bonds Unsaturated compounds because they don’t have full number of hydrogens To name alkynes by IUPAC system use same rules as alkenes but use “yne” ending instead of “ene”.

Isomers Structural Isomers Geometric Isomers Compounds that have the same molecular formula but different molecular structures Differ in physical properties (BP & MP) and reactivity Ex: C4H10 can be butane or 2 methyl propane Geometric Isomers Differ only in the geometry of their substituents. Alkenes are fairly structured due to their double bonds. Therefore, there are two arrangements of the substituents, cis and trans, that are noted in naming. Cis configurations- place the substituents on the same side of the double bond Trans configurations-place the substituents on the oppostie sice of the double bond. Sample Problems 25.3 & 25.4 on pg 1064

Stereoisomers Compounds of the same molecular structure that differ only in the arrangement of the atoms in space. Contain a asymmetrical carbon Compounds are nonsuperimposable mirror images of each other.

Alicyclic In some cases, the two ends are attached to form a ring. Rings contain 3 to 20 carbons, but most are 5 or 6 carbons. Naming for Alicyclic compounds are the same as alkanes except that you add cyclo to the front of the parent name. Practice Problems #105 pg 77.

Aromatic Unsaturated rings of carbon that have double bonds so not as many hydrogens as possible. Benzene is the most simple form that has the molecular formula C6H6. Other aromatics either have the benzene as the parent part of the compound or the benzene is a substituent on a hydrocarbon chain. If the benzene is the main part of the compound, the substituents are then named as usual picking one of the substituents as position 1. If the benzene is a substituent is part of a chain then it is called a phenyl group.

Polar Single Bond Functional Groups Compounds that only have single bonds but now include many other atoms in addition to carbon and hydrogen. Main Types include… Halocarbons Alcohols and Phenols Ethers Amines

Halocarbons Compounds of carbon and hydrogen that also contain covalently bonded fluorine, chlorine, bromine or iodine (halogens). These compounds are also called alkyl halides due to their common names. Have higher boiling points than hydrocarbons Using IUPAC naming rules, all have single bonds so parent chain name is the same as alkanes. Then the “ine” is taken off of the halogen and replaced with “o” and put in front of the parent name. A number is then placed in front of the halogen depending on where attaches to the chain. Practice problem #23 and 24 pg 1098

Alcohols and Phenols Alcohol have a OH group attached to a carbon in a hydrocarbon chain and Phenols have an OH group attached to a hydrocarbon ring. Boil at higher temps than hydrocarbons and halocarbons Some are soluble in water (those with 4 or less carbons). Both IUPAC and common names are used for Alcohols. Naming with IUPAC system: find the longest chain of carbons that includes the one attached to the OH, replace the “e” of the parent name with “ol”. If there are more than 1 OH substituents the ending changes to 2-diol, 3-triol, 4-tetrol Common names have the alkyl group followed by “alcohol”. It can be a primary, secondary or tertiary alcohol due to the number of substituents attached to the carbon the OH is attached to. Practice problems #77 and 78 pg 74

Ethers Compounds in which oxygen is bonded to two carbon groups or chains. Naming is fairly simple… the alkyl groups attached to either side of the oxygen are named in alphabetical order and followed by the word ether. When both groups are the same on each side the ether is symmetrical and a di is put on the front of the name Practice problems #

Amines A compound that has a nitrogen attached to at least one hydrocarbon group. Primary amines only have one group (R-NH2) Secondary amines have two groups (R-NH-R) Tertiary amines have three groups (R-N-R) Naming is the same as ethers except you use the word amine instead of ether at the end R

Carbon-Oxygen Double Bond Functional Groups Compounds that contain a carbonyl group which is a carbon that is joined with an oxygen by a double bond. Main types include… (bottom half of Table 25.4 pg 1071) Aldehydes Ketones Carboxylic Acid Esters Amides

Aldehydes Compound in which the carbon of the carbonyl group is always joined to at least one hydrogen. Those with 3 or less carbons are soluble in water. Have higher boiling points… Using the IUPAC system, find the longest hydrocarbon chain that contains the carbonyl group. The “e” ending of the hydrocarbon is replaced by “al”.

Ketones Compound in which the carbon of the carbonyl group is joined to two other hydrocarbon groups Using the IUPAC system, find the longest hydrocarbon chain that contains the carbonyl group. The “e” ending of the hydrocarbon is replaced by “one”. If the carbonyl group of a ketone could occur at several places on the chain, then its position is designated by the lowest possible number. Practice problem #44 pg 1099.

Carboxylic Acids Compounds with a carboxyl group, which is a carbonyl group attached to a hydroxyl group (OH). Weak acids because they ionize only slightly in solution to give a carboxylate ion and a hydrogen ion. Using the IUPAC system, replace the “e” ending of the longest continuous carbon chain containing the carboxyl group with the ending “oic acid”. Many continuous chain carboxylic acids were first isolated from fats and are called fatty acids. Common names are often used more than IUPAC names. (Figure 25.17 on pg 1074) Practice problems #43 pg 1099.

Esters Compounds that contain a carbonyl group and an ether link to the carbonyl carbon. Many esters have pleasant, fruity odors and give most fruits their lovely odors. Lower boiling points… Can be hydrolyzed by the addition of water to produce a carboxylic acid and an alcohol. Using the IUPAC system, find the longest chain that has the carboxyl group and add a “oate” on the end instead of an “e”. Add the alkyl group from the other side of the oxygen to the front of the parent name.

Amides A compound that has a nitrogen attached to a carbonyl group. Primary amides only bond to hydrogens and the carbonyl group (carbonyl-NH2) Secondary amides have one hydrogen and one carbon group bonded to the nitrogen (carbonyl-NH-R) Tertiary amides have two carbon groups bonded to the nitrogen (carbonyl-N-R) Practice Problems #39-40 pg 1099. R

Additional substituents… Isopropyl Prefix iso is used when there is a methyl group on the carbon second from the unsubstituted end of the longest chain Isobutyl The carbon joining this alkyl group to another group is bonded to one other carbon, it is a primary carbon Sec-butyl The carbon joining this alkyl group to another group is bonded to two other carbons, it is a secondary carbon. Tert-butyl The carbon joining this alkyl group to another group is bonded to three other carbons, it is a tertiary carbon Vinyl When used as an alkl group in giving compounds common names ethene (without one hydrogen) is called a vinyl Phenyl When benzene is used as an alkyl group.