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Organic chemistry part II

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1 Organic chemistry part II

2 Alcohols Any organic compound in which the hydroxyl functional group (–OH) is bound to a saturated carbon atom. The suffix -ol appears in all substances where the hydroxyl group is the functional group with the highest priority. The term alcohol originally referred to the primary alcohol ethanol (ethyl alcohol), the predominant alcohol in alcoholic beverages. The general formula is CnH2n+1OH.

3 Alcohols In substances where a higher priority group is present the prefix hydroxy- will appear. The suffix -ol in non-systematic names (such as paracetamol or cholesterol) also typically indicates that the substance includes a hydroxyl functional group and, so, can be termed an alcohol. But many substances, particularly sugars (examples glucose and sucrose) contain hydroxyl functional groups without using the suffix.

4 Rules for naming the alcohols
Find the longest chain containing the hydroxy group (OH). If there is a chain with more carbons than the one containing the OH group it will be named as a subsitutent. Place the OH on the lowest possible number for the chain. With the exception of carbonyl groups such as ketones and aldehydes, the alcohol or hydroxy groups have first priority for naming. When naming a cyclic structure, the -OH is assumed to be on the first carbon unless the carbonyl group is present, in which case the later will get priority at the first carbon.

5 Rules for naming the alcohols
Remove the final -e from the parent alkane chain and add -ol. When multiple alcohols are present use di, tri, et.c before the ol, after the parent name. ex. 2,3-hexandiol. If a carbonyl group is present, the -OH group is named with the prefix "hydroxy," with the carbonyl group attached to the parent chain name so that it ends with -al or -one.

6 Primary alcohols In a primary (1°) alcohol, the carbon which carries the -OH group is only attached to one alkyl group.

7 Secondary alcohols In a secondary (2°) alcohol, the carbon with the -OH group attached is joined directly to two alkyl groups, which may be the same or different.

8 Tertiary alcohols In a tertiary (3°) alcohol, the carbon atom holding the -OH group is attached directly to three alkyl groups, which may be any combination of same or different.

9 Properties of Alcohols
Two reactive covalent bonds, the C–O bond and the O–H bond. The electronegativity of oxygen is substantially greater than that of carbon and hydrogen. Consequently, the covalent bonds of this functional group are polarized so that oxygen is electron rich and both carbon and hydrogen are electrophilic.

10 Properties of Alcohols
The dipolar nature of the O–H bond is such that alcohols are much stronger acids than alkanes (by roughly 1030 times), and nearly that much stronger than ethers (oxygen substituted alkanes that do not have an O–H group). The most reactive site in an alcohol molecule is the hydroxyl group, despite the fact that the O–H bond strength is significantly greater than that of the C–C, C–H and C–O bonds, demonstrating again the difference between thermodynamic and chemical stability.

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12 https://www2. chemistry. msu. edu/faculty/reusch/virttxtjml/alcohol1

13 Phenols Class of chemical compounds consisting of a hydroxyl group (—OH) bonded directly to an aromatic hydrocarbon group. The simplest of the class is phenol, C6H5OH. Phenolic compounds are classified as simple phenols or polyphenols based on the number of phenol units in the molecule.

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17 Carboxilic acids Contains a carboxyl group (C(O)OH).
The general formula of a carboxylic acid is R–C(O)OH, with R referring to the rest of the molecule. The –e ending is removed from the name of the parent chain and is replaced -anoic acid. Since a carboxylic acid group must always lie at the end of a carbon chain, it is always is given the #1 location position in numbering and it is not necessary to include it in the name.

18 http://chemwiki. ucdavis

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20 http://www. science. oregonstate. edu/~gablek/CH336/Chapter20/acidders

21 Ethers Class of organic compounds that contain an ether group — an oxygen atom connected to two alkyl or aryl groups—of general formula R–O–R′. The ether functional group does not have a characteristic IUPAC nomenclature suffix, so it is necessary to designate it as a substituent.

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23 http://www. masterorganicchemistry

24 Esters Chemical compounds derived from an acid (organic or inorganic) in which at least one –OH (hydroxyl) group is replaced by an –O–alkyl (alkoxy) group. Usually, esters are derived from a carboxylic acid and an alcohol. Esters are named as if the alkyl chain from the alcohol is a substituent. No number is assigned to this alkyl chain. This is followed by the name of the parent chain from the carboxylic acid part of the ester with an –e remove and replaced with the ending –oate.

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28 Aldehydes Organic compound containing a formyl group, a functional group with the structure −CHO, consisting of a carbonyl center (a carbon double-bonded to oxygen) with the carbon atom also bonded to hydrogen and to an R group, which is any generic alkyl or side chain. The group without R is the aldehyde group or formyl group.

29 Aldehydes The IUPAC system of nomenclature assigns a characteristic suffix -al to aldehydes. For aldehydes common parent chain names, similar to those used for carboxylic acids, are used and the suffix –aldehyde is added to the end.

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31 Ketones Organic compound with the structure RC(=O)R', where R and R' can be a variety of carbon-containing substituents. The IUPAC system of nomenclature assigns a characteristic suffix of -one to ketones. A ketone carbonyl function may be located anywhere within a chain or ring, and its position is usually given by a location number.

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33 http://www. masterorganicchemistry

34 Carbohydrates Biological molecule consisting of carbon, hydrogen and oxygen atoms, usually with a hydrogen–oxygen atom ratio of 2:1 Empirical formula Cm(H2O)n Carbohydrates are polyhydroxy aldehydes ketones.

35 Organic chemistry part II


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