RGANI EMISTRY hemistry 11 rganic molecules are everywhere! Some common examples: Sucrose (sugar) Methane (natural gas) Butane (lighter fluid) Plastic Acetic Acid (vinegar) Ethanol (fuel additive) What Makes arbon so Special? (See pages 25-3, 25-4) The structure of arbon allows it to make 4 bonds. It ALWAYS makes 4 bonds! It can bond with itself to make long chains or rings. That s why there are so many organic compounds. About 90000 inorganic vs. millions of organic compounds. More synthesized every day! The Alkanes (See pages 25-4 and 25-5) ontain only single bonds. Are also called. Filled with only single bonds in the arbon chain. General formula is n 2n+2. Use a plus the ending. For example: Propane 3-methyl-5-ethyl-6-propyldecane Alkyl Groups (See pages 25-6 and 25-7) Attach themselves to the longest parent organic chain. Same prefixes as Alkenes, but use an ending instead. Naming Alkanes (See pages 25-7 to 25-10) Find the longest chain of continuous arbons bound together. Use prefixes to indicate number of arbons in the longest chain. Use the suffix (ending) to indicate that only single bonds are present. Number the arbon chain to make the lowest possible numbers for attached alkyl groups. Use numbers and prefixes to indicate the position of any branched chains (in alphabetical order). 1
2 2 3 methyl hexane 2 2 1 Longest chain is 6 arbons, therefore prefix. nly single bonds, therefore ending. Numbering the chain: nly one Alkyl group consisting of one arbon. Use prefix. Use the ending on the attached Alkyl group. We need to give it the lowest number possible. Therefore, on the of the parent chain. Section 25, problems 1 to 7 yclic ydrocarbons (See pages 25-11 to 25-13) There is a carbon ring present Name just like before, only difference: The parent chain gets the prefix added to it No number is required when only one branch is off the ring. For example: Additional naming rules: (See page 25-12) If there are two or more substituents on a ring, numbers must be used to indicate their positions. ne of the substituents is always assigned position number 1, and starting at position 1, the chain is numbered either clockwise or counterclockwise so as to give the other substituents on the ring the smallest possible numbers. 2 Alkenes and Alkynes (See pages 25-14 to 25-18) Unsaturated hydrocarbons. Alkenes = at least Alkynes = at least When naming, follow the same process as with alkanes except Use different ending (alkene) or (alkyne). Need a number to indicate where the double or triple bond is. If the double bond is between arbon 2 and arbon 3, use the number 2 in the name. 2 2 2
Section 25, problems 8 to 12 Drawing ydrocarbons W.S. Geometry of Alkenes Isomers: Molecules with the same formula, but different arrangement of the atoms. is-trans Isomerization Double bonds trap a molecule in a specific shape. When different groups are across a double bond, different isomers form. 3 2 2 This presents us with two possibilities for the previous example: 3 2 2 is = the same side and 3 2 2 The non-hydrogen groups are on the same side of the double bond. Trans = across (like the Trans anada ighway) The non-hydrogen groups are across from each other in the double bond. This creates similar molecules with distinctively different properties. Melting/boiling point, reactivity, stability, polarity. onsider the two isomers for 2-pentene: 3 2 cis-2-pentene 3 2 trans-2-pentene is-trans Isomerization W.S. Study for your quiz: ydrocarbons Functional Groups Up to now, organic compounds have only included two elements: and. There are many other organic compounds that contain other elements or groups of elements. The replacement of an in a parent chain with one of these groups produces other compounds with their own set of chemical and physical properties. We call these. Each of these compounds have a unique but familiar set of naming rules. 3
Alcohols: (See page 26-3 to 26-5) Functional Group: ydroxy (-) hange to ending. Ethers: (See page 26-5 to 26-6) Functional Group: Alkyl group on each side of an xygen. Use in name. Aldehydes: (See page 26-6 to 26-8) Functional Group: Double bonded xygen on terminal arbon. hange to ending. Ketones: (See page 26-6 to 26-8) Functional Group: Double bonded xygen on parent chain. hange to ending. 2 2-butanol 2 methoxyethane 2 propanal 2 2-butanone Section 26, problems 1-4 More Functional Groups rganic Acids: (See page 26-8 to 26-9) Functional Group: arboxyl (-) hange to ending. Esters: (See page 26-9 to 26-11) Functional Group: Alkyl group replaces the in the organic acid. hange to ending. Amines: (See page 26-11 to 26-13) Functional Group: Amino (-N 2 ) Primary: use prefix. 2 propanoic acid 2 methyl propanoate 2 N 2 2-aminobutane Secondary and tertiary: use for the alkyl groups. hange to ending. Amides: (See page 26-13 to 26-14) Functional group: Amide group (-N 2 ) hange to ending. order alogenated ydrocarbons: (See page 26-14 to 26-16) Functional Group: alogen group replaces an in the parent chain. hange the ine ending to in the halogen. N 2 ethylmethylamine N 2 2 dimethylpropylamine 2 3-methylbutanamide F N 2 F 2,3-difluorobutane Section 26, problems 5-10 Read: Preparation of Esters Lab Aromatic ompounds (See pages 27-3 to 27-4) Based on the ring: or A ring consisting of six arbon atoms joined by alternating single and double bonds. 4
Naming Aromatic ompounds (See pages 27-4 to 27-8) The Benzene ring is the parent compound. The ending is always. When the ring has two substituents, the prefixes,, and are used to describe the positions of the substituents. ortho (o-): adjacent positions. meta (m-): separated by 1 arbon atom. para (p-): across from one another on the ring. methylbenzene m-dimethylbenzene Three or more substituents must be numbered. Lowest numbers required (just like cyclic alkanes/enes/ynes). Section 27, problems 1-4 What is on the exam? Naming, drawing, and identifying: Aliphatic ompounds: Alkanes, alkenes, and alkynes yclic hydrocarbons is/trans Isomerism Saturated vs. Unsaturated hydrocarbons Alcohols Ethers Aldehydes Ketones rganic Acids Esters Amines Amides alogenated ydrocarbons Aromatic compounds: Benzene rings Structural Isomers ondensed ring structures Esterification reaction (lab) Predicting and naming products (ester) 5