For the functional groups on the 2 nd part of Table 2. It is usually more challenging to identify and draw these functional groups correctly, because they are kind of similar. More practice is needed. Aldehyde and ketone are similar in terms of their structures and properties. Ketone can also be in a cyclic structure. The last four functional groups are related in terms of structures and chemical properties. The other three, ester , anhydride and amide, are all derivatives of carboxylic acid, meaning they can be prepared with carboxylic acid as the starting material.
All Rights Reserved. Skip to content Functional groups are the most reactive parts in organic compounds, and determine the major properties of compounds.
I will be highly grateful. Are you sure about the positions of Br and NO2 in this compound you have described. As it is a ether group, the functional group will be at the 5 position. Its name is 3-Nitro 5-Bromo benzyl methyl ether. Functional groups are named in alpha order if equivalent positions 3 or 5. Therefore 3-bromo, 5-nitro methoxybenzene or, since anisole IS recognized, 3-bromo, 5-nitro anisole. This entire website is an amazing resource for MCAT studying.
I would like to use the diagram from the following page in a coursepack for a course to be held at Fleming College in Ontario, Canada this fall:.
I then need to give some sort of example and then justify this but i am not sure how to do so, could you please help? Thankyou :. I would move thiols to the second list, and move epoxides, imines, and acid chlorides to the first list. There is absolutely no point in putting a list of names associated with molecular configuration unless you give a description of why a particular functional group is important in chemistry.
One needs real scientific insight not just another lesson in learning a language. I am having a tough time these days justifying calling a hydroxyl group and alcohol group. Draw one example each of compounds fitting the descriptions below, using line structures. Be sure to designate the location of all non-zero formal charges. All atoms should have complete octets phosphorus may exceed the octet rule. There are many possible correct answers for these, so be sure to check your structures with your instructor or tutor.
While the IUPAC system is convenient for naming relatively small, simple organic compounds, it is not generally used in the naming of biomolecules, which tend to be quite large and complex. Naming an organic compound usually begins with identify what is referred to as the 'parent chain' , which is the longest straight chain of carbon atoms.
CH 4 is called methane , and C 2 H 6 ethane. The table below continues with the names of longer straight-chain alkanes: be sure to commit these to memory, as they are the basis for the rest of the IUPAC nomenclature system and are widely used in naming biomolecules as well. Names for straight-chain alkanes:. When the substituents are small alkyl groups, the terms methyl , ethyl , and propyl are used.
Other common names for hydrocarbon substituent groups are isopropyl, tert -butyl and phenyl. The IUPAC name for straight-chain hydrocarbons is always based on the longest possible parent chain , which in this case is four carbons, not three.
Cyclic alkanes are called cyclopropane, cyclobutane, cyclopentane, cyclohexane, and so on:. In the case of multiple substituents, the prefixes di , tri , and tetra are used. Functional groups have characteristic suffixes.
Alkenes are designated with an 'ene' ending, and when necessary the location and geometry of the double bond are indicated. Compounds with multiple double bonds are called dienes, trienes, etc. Ethers and sulfides are designated by naming the two groups on either side of the oxygen or sulfur. Note that the structures below are both based on a three-carbon propan parent chain.
For esters, the suffix is 'oate'. The group attached to the oxygen is named first. All of the examples we have seen so far have been simple in the sense that only one functional group was present on each molecule.
There are of course many more rules in the IUPAC system, and as you can imagine, the IUPAC naming of larger molecules with multiple functional groups, ring structures, and substituents can get very unwieldy very quickly. You can see why the IUPAC system is not used very much in biological organic chemistry - the molecules are just too big and complex.
The compounds acetic acid, chloroform, and acetone are only a few examples. In biochemistry, nonsystematic names like 'cocaine', 'capsaicin', 'pyruvate' or 'ascorbic acid' are usually used, and when systematic nomenclature is employed it is often specific to the class of molecule in question: different systems have evolved, for example, for fats and for carbohydrates.
We will not focus very intensively in this text on IUPAC nomenclature or any other nomenclature system, but if you undertake a more advanced study in organic or biological chemistry you may be expected to learn one or more naming systems in some detail.
Draw line structures of the following compounds, based on what you have learned about the IUPAC nomenclature system:. Often when drawing organic structures, chemists find it convenient to use the letter 'R' to designate part of a molecule outside of the region of interest. If we just want to refer in general to a functional group without drawing a specific molecule, for example, we can use 'R groups' to focus attention on the group of interest:. The 'R' group is a convenient way to abbreviate the structures of large biological molecules, especially when we are interested in something that is occurring specifically at one location on the molecule.
For example, in chapter 15 when we look at biochemical oxidation-reduction reactions involving the flavin molecule, we will abbreviate a large part of the flavin structure which does not change at all in the reactions of interest:.
As an alternative, we can use a 'break' symbol to indicate that we are looking at a small piece or section of a larger molecule. This is used commonly in the context of drawing groups on large polymers such as proteins or DNA. Finally, 'R' groups can be used to concisely illustrate a series of related compounds, such as the family of penicillin-based antibiotics. Using abbreviations appropriately is a very important skill to develop when studying organic chemistry in a biological context, because although many biomolecules are very large and complex and take forever to draw!
As a rule, you should never abbreviate any atom involved in a bond-breaking or bond-forming event that is being illustrated: only abbreviate that part of the molecule which is not involved in the reaction of interest. If you are unsure whether to draw out part of a structure or abbreviate it, the safest thing to do is to draw it out. Carbon dioxide and the oxygen of water are colored red and blue respectively to help you see where those atoms are incorporated into the products.
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