Alcohol phenol and ether

Nomenclature of Alcohols We know alcohols are of three major classes. They are: • Monohydric Alcohol • Dihydric Alcohol • Trihydric Alcohol We will now discuss the nomenclature of these alcohols. 1) Monohydric Alcohol Monohydric alcohols have the general formula C nH 2n+1OH where n = 1, 2, etc. We can also represent them as R-OH where R describes an alkyl group. There are three systems for the nomenclature of Monohydric Alcohol. • Common System: In this system, we name the monohydric alcohols as Alkyl Alcohol. We get their names by adding the name alcohol after the name of the alkyl group present in the 3-OH has one methyl group with an alcohol group. Hence, we call it Methyl Alcohol. • Carbinol System: In this system, methyl alcohol (CH 3OH) gets the name Carbinol while other alcohols get their names as alkyl or aryl derivatives of carbinol. Example: CH 3-CH 2-OH is methylcarbinol and CH 3-CH 2-CH 2-OH is Ethylcarbinol. • IUPAC System: In IUPAC nomenclature, we term the alcohols as Alkanols. We get the name of any alcohol by replacing the last ‘e’ from the name of the corresponding alkane by the suffix ‘–ol’. Then, we select the longest carbon chain containing the OH group as the parent chain. We, then, number the longest chain in such a way that the carbon atom carrying the OH group gets the smaller number. After. this, we show the position of the substituents by suitable numbers allotted to their respective carbon atom. Example: The compound CH 3-OH is Methyl Alcohol bu...

Monohydric i.e. Dihydric Polyhydric Contain three and more than three hydroxyl group. Monohydric alcohols are of three types. PREPARATION OF ALCOHOLS 1. From Alkanes Alkanes having tertiary carbon on oxidation with cold alkaline KMnO 4 give tertiary alcohol. 2. From Alkenes Alkenes can be converted into alcohol by the following reactions: 3. From alkyl halides Alkyl halides give alcohol with KOH/NaOH or with moist Ag 2O. 4. Reduction of aldehydes and ketones (a) Reduction by reducing agents (i) Aldehyde gives primary alcohol (ii) Ketone gives secondary alcohol Reducing agents (ii) LiAlH 4 (ii) NaBH4 (iii) Na/C 2H 5OH (iv) Metal (Zn, Fe or Sn)/Acid (HCl, dil H 2SO 4 or CH 3COOH) (v) (a) Aluminium isopropoxide/isoproppylalcohol (b) H2O (vi) H 2/Ni NaBH 4 and aluminium isopropoxide reduces only carbonyl group and has no effect on any other group. Reducing with aluminium isopropoxides is known as Meerwein – Ponndorf Verley (MPV) reduction. LiAlH 4 has no effect on double and triple bonds but if compound is β - aryl, α, β - unsaturated carbonyl compound then double bond also undergoes reduction. (b) Reduction by Grignard reagents Addition followed by hydrolysis Methanol can not be prepared by this method. 5. Reduction of carboxylic acid, Acid chlorides and esters: (a) Reduction by LiAlH 4 G = OH (acid) G = Cl (acid chloride) G = OR′ (ester) (b) Reduction by BH 3 Carboxylic acids and esters are reduced in to primary alcohol by BH 3. (c) Bouveault – Blanc reaction 6. From aliphat...

Alcohols, Phenols, and Ethers • Chemist r y Submitted by:­ Abdul Noor XII Science(2012­13) • Phenols, and Ethers Alcohols and phenols are formed when a hydrogen atom in a hydrocarbon, aliphatic and aromatic respectively, is replaced by –OH group.An alcohol contains one or more hydroxyl (OH) group(s) directly attached to carbon atom(s), of an aliphatic system (CH3OH) while a phenol contains –OH group(s) directly attached to carbon atom(s) of an aromatic system (C6H5OH). The substitution of a hydrogen atom in a hydrocarbon by an alkoxy or aryloxy group (R–O/Ar–O) yields another class of compounds known as ‘ethers’, for example, CH3OCH3 (dimethyl ether). • Di, Tri or Polyhydric Compounds • C sp3 − OH bond: Primary, secondary and tertiary alcohols: Allylic alcohols: • containing C sp2 − OH bond: • classified as simple or symmetrical, if the alkyl or aryl groups attached to the oxygen atom are the same, and mixed or unsymmetrical, if the two groups are different. Diethyl ether, C2H5OC2H5, is a symmetrical ether whereas C2H5OCH3 and C2H5OC6H5 are unsymmetrical ethers. • common name of an alcohol is derived from the common name of the alkyl group and adding the word alcohol to it. For example, CH3OH is methyl alcohol.According to IUPAC system (Unit 12, Class XI), the name of an alcohol is derived from the name of the alkane from which the alcohol is derived, by substituting ‘e’ of alkane with the suffix ‘ol’. The position of substituents are indicated by numerals. For this, the l...