Nomenclature of Alcohols and Phenols

The lUPAC system provides unique names for alcohols, based on rules that are similar to those for other classes of compounds. In general, the name carries the -ol suffix, together with a number to give the location of the hydroxyl group. The formal rules are summarized in the following three steps  

Name the longest carbon chain that contains the carbon atom bearing the — OH group. Drop the final -e from the alkane name and add the suffix -ol to give the root name. 

Number the longest carbon chain starting at the end nearest the hydroxyl group, and use the appropriate number to indicate the position of the —OH group. (The hydroxyl group takes precedence over double and triple bonds.) 

Name all the substituents and give their numbers, as you would for an alkane or an alkene. 

In the following example, the longest carbon chain has four carbons, so the root name is butanol. The —OH group is on the second carbon atom, so this is a 2-butanol. The complete lUPAC name is l-bromo-3,3-dimethyl-2-butanol. The new lUPAC positioning of numbers would place the 2 next to the group it locates ( ol), giving the name l-bromo-3,3-dimethylbutan-2-ol. 

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In the IUPAC system of nomenclature, the suffix for alcohols is -ol. Alcohols are classified as primary, secondary, or tertiary depending on whether one, two, or three organic groups are attached to the hydroxyl-bearing carbon. The nomenclature of alcohols and phenols is summarized in Secs. 7.1-7.3. 

Structure and Classification of Alcohols 425 10-3 Nomenclature of Alcohols and Phenols 427 10-4 Physical Properties of Alcohols 430 10-5 Commercially Important Alcohols 433 10-6 Acidity of Alcohols and Phenols 435 10-7 Synthesis of Alcohols Introduction and Review 438 Summary Previous Alcohol Syntheses 438 10-8 Organometallic Reagents for Alcohol Synthesis 440 10-9 Addition of Organometallic Reagents to Carbonyl Compounds 443... 

Production of phenol and acetone is based on liquid-phase oxidation of isopropylbenzene. Synthetic fatty acids and fatty alcohols for producing surfactants, terephthalic, adipic, and acetic acids used in producing synthetic and artificial fibers, a variety of solvents for the petroleum and coatings industries—these and other important products are obtained by liquid-phase oxidation of organic compounds. Oxidation processes comprise many parallel and sequential macroscopic and unit (or very simple) stages. The active centers in oxidative chain reactions are various free radicals, differing in structure and in reactivity, so that the nomenclature of these labile particles is constantly changing as oxidation processes are clarified by the appearance in the reaction zone of products which are also involved in the complex mechanism of these chemical conversions. 

The prefix hydroxy- should be universally adopted to express the alcohol or phenol function. In German and several other languages (presumably under the influence of the Beilstein nomenclature) the prefix oxy- is used (Oxysauren = hydroxy acids, OxybenzoU = hydroxybenzenes). This is a relic of the old addition nomenclature, oxy- meaning an oxygen atom (trioxymethylene, phosphorus oxychloride), but organic chemical nomenclature now generally follows the principle of substitution. 

In 1912, Grafe takes over the confused nomenclature of previous studies in regarding Kaffeol , Kaffeon , Cafeone and KaffeeoP as the group of aromatic substances obtained with a yield of 0.3-0.45% by hydrodistillation of roast coffee powder and ether extraction. He contributes no notable advance in mentioning that 38% of the extract consists of acetic and valerianic acid, that 50% is furfurylic alcohol and other furans, and that the rest is a mixture of phenols with the odor of creosote and a pyridinic derivative that could be responsible for coffee s specific aroma. His article includes a comparative analysis of the components of normal coffee and decaffeinated coffee, the method for which had recently been patented. 

The glycol ethers formed by reaction of an alcohol or phenol with ethylene or propylene oxide to yield a solvent with both an alcoholic and ether functional groups are discussed in Chapter 13. Major producers of the alcoholic solvents include BASF Corporation, Eastman Chemical Company, Exxon Chemical Company, Hoechst Celanese Company, Shell Chemical Company, and Union Carbide Corporation. This chapter will discuss the naming nomenclature for the alcohols, their physical properties, the various industrial uses, possible environmental concerns, and the safe handling of the alcohols. 

A number of small changes have been made so that Organic Experiments reflects the very latest and best of organic chemistry. Nomenclature revision is a continuous process. Gradually names such as isoamyl alcohol are being replaced by their lUPAC equivalents, but slavish adherence to those rules is not followed phenol is still phenol (and not benzenol). 

Where the molecule contains both a double bond and an OH group, the OH group takes precedence in numbering the chain (at the end of this section on nomenclature, there will be a complete list of priorities). So 4.18 is named as 2-propene-l-ol. Its common name is allyl alcohol. We have already met phenol, 4.19—when there is more than one OH group or where the OH group does not have the highest priority and is named as a substituent, we use the term hydroxy. So, 4.20 is 1,3-dihydroxybenzene. 

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