Organic Terminology

 

FUCTION GROUPS AND COMPOUND CLASSIFICATION

Alcohol: An alcohol is any compound with a hydroxyl group bonded to an alkyl group. It is named by the prefix of the alkyl followed by the suffix 'anol'.

Example: C2H5OH - Ethanol

Aldehyde: An aldehyde is any compound with the CHO function group attached to either another group, compound or hydrogen. These are often made by oxidising alcohols under a copper catalyst. It is most commonly seen as R-(O=C-H)

Example: HCHO - Formaldehyde

Alkyl: An alkyl is a chain of only carbon and hydrogen atoms. This is generally represented by C(n)H(2n + 1). Here is a table to help with the naming of alkyls (provided by wikipedia encyclopedia, www.wikipedia.org)

Number of carbons	1	2	3	4	5	6	7	8	9	10	11	12
Prefix	Meth	Eth	Prop	But	Pent	Hex	Hept	Oct	Non	Dec	Undec	Dodec

Amide: An amide is a function group that has a carbonyl group bonded to a nitrogen atom in another group. This can be represented as R1(CO)NR2R3

Example: CH3CONH2 - Acetamide

Amine: An amine is any organic compound containing nitrogen as the main atom in the functional group. There are 3 types of amines; Primary, Secondary, and Tertiary. The primary is generaly shown as R1(NH2), the secondary as R1(NH)R2, and the tertiary as R1(N)R2R3.

Ketone: A ketone is a functional group that has a carbonyl group linked to two other carbon atoms from another functional group. This is generally represented by R1(CO)R2

Example: CH3(CO)C2H5 - Methyl Ethyl Ketone

Hydroxyl: A hydroxyl group is a substituent functional group with the formula -OH. Molecules containing hydroxyl groups are usually known as alcohols.

Example: CH3OH - Methanol

Nitro/Nitrate: A nitro group is a substituent group with the formula -NO2. Compounds with nitro groups on them are generaly explosive.

Example: C6H2(NO2)3CH3 - TriNitroToluene (TNT)

Nitrite: A nitrite is another substituent group but has the formula -ONO. It is commonly expressed as R-O-N=O.

Example: C5H11ONO - Amyl Nitrite

 

TYPES OF REACTIONS

Nitration: A nitration reaction is where a mixture of nitric and sulfuric acids are used to remove a hydrogen atom from a compound and replace it with a nitrate function group. During nitration, nitric acid disociates into NO2+ and OH- in the presence of sulfuric acid. The OH- ion takes up the hydrogen atom that was removed from the compound and forms water.

H2SO4 + HNO3 ---> H2SO4 + NO2 + OH

Example: C6H6 + HNO3/H2SO4 ----> C6H5NO2 + H2O (Nitration of benzene into nitrobenzene)

Reduction: A reduction is when a molecule, atom, or ion takes up an extra electron. This usually causes the loss of an oxygen atom but a gain of a hydrogen atom. The most feasible reducing agent that a home chemist can obtain is a Transitional metal chloride (in acidic solution). In normal reductions, the metal chloride is produced and used in one reaction.

Example: C6H5NO2 + Sn + 2HCl ----> C6H5NH2 + SnCl2 + H2O

Oxidation: An oxidation is when a molecule, atom, or ion gives up an electron. This usually causes the loss of a hydrogen but the gain of an oxygen. This is pretty much the exact opposite of reduction. There are many different oxidisers out there but the most common for organic chemistry are potassium permanganate, sodium dichromate, and nitric acid.

Example: C6H5CH3 + 2KMnO4(aq) ----> C6H5COOK + KOH(aq) + 2MnO2(s) + H2O