THE HIMALAYAN TALK: PALASH BISWAS TALKS AGAINST CASTEIST HEGEMONY IN SOUTH ASIA

THE HIMALAYAN TALK: PALASH BISWAS TALKS AGAINST CASTEIST HEGEMONY IN SOUTH ASIA INDIA AGAINST ITS OWN INDIGENOUS PEOPLES

PalahBiswas On Unique Identity No1.mpg

Saturday, August 9, 2014

By Excalibur Stevens Biswas Why people drink hooch??Why hooch business is on boom??? I asked a guy once,"why you drink this poison it will kill you", he replied ,"the system has murdered us so we are already dead.".

Status Update


By Excalibur Stevens Biswas


Why people drink hooch??Why


hooch business is on boom???

I asked a guy once,"why you drink this poison it will kill you", he replied ,"the system has murdered us so we are already dead.".


Excalibur Stevens Biswas


People don't like those people who drink hooch, because its cheap , it gives a rotten smell and also it's symbol of low class and status.


Hooch is a colloquial term for alcoholic beverages (also spelled hootch).


Country liquor (CL) market estimated at 220 million cases (of 9 litres each) in 2008


Retail value Rs 25,000 crore.


In last five years, country liquor consumers have taken to cheap IMFL.


This explains why country liquor market growth has been subdued.


Southern states have banned sale of country liquor.


UP, Maharashtra Bihar and West Bengal big markets for country liquor.


India intoxicated About 60 million (5% approx.) Indians are alcoholics. This equals the population of France.


Two-thirds of the alcohol consumed in India is illegal hooch


More than half of all drinkers in India fall in hazardous drinking category 95% of beverages drunk in India are IMFL, licensed country liquor, and illicit spirits.


Official records show alcohol sales have grown 8% in the past 3 yrs. These figures don't include illegal liquor sales


Govt stats show only 21% of adult Indian men and 2% of women drink


Percentage of drinking population aged under 21 years up from 2% to more than 14% in 15 years


Average age of initiation dropped from 19 years to 13 years in two decades


Employers in poor communities sometimes pay wages in alcohol rather than cash


Hospital admissions WHO says Alcohol-related problems account for more than a fifth of hospital admissions


18% of psychiatric emergencies


More than 20% of all brain injuries


60% of all injuries reporting to emergency rooms


Hooch economics A NIMHANS study shows in many poor households of Karnataka, average monthly expenditure on alcohol more than average monthly salary


Ban on country liquor in Maharashtra saw wife beating cases drop by 35% in 2010


How much does a hooch pouch cost in Bengal? As little as Rs 10 for half a litre


Maximizing profits Bootleggers, working from homes, warehouses and forests, can turn 1 litre of genuine alcohol into 1,000 litres of bootlegged swill with chemicals and additives that usually cause no harm, but on occasion can lead to tragedy


Typical hooch poisoning symptoms


Vomiting, piercing headaches, frothing at the mouth Complaints of burning chest and severe stomach pain Spurious liquor can induce coma, blindness and death


Hooch or commonly known as homemade alcohol which is made by the mixture of rotten rice,rotten fruit juice and sugar and its mixed with high amount of urea and is boiled until it looks like clear water.


The composition,however, looks poisonous drink. But it plan an important role in black economy and the hooch dealers do play major role in local politics and local underworld;as the amount earned by selling hooch is huge as its consumed by most people who come from lower society, and unfortunately in India 70% of population are below poverty line.


And these people are customers of these hooch dealers, so in such a way they earn a lot, and why these people go to hooch dealers, because they provide good booz at low cost ,because any premium alcohol costs near about 75 rupees approx(180 ml) and same amount of hooch comes for 20 rupees and it gives a nice booz.


Its a nice deal for the lower class.

Now who are the consumers of hooch, mostly come from lower end of society and specifically the people who do lot of manual labour for eg:- rickshaw pullers , building labours ,small shopkeepers who can't afford premium or country liquor.


They consume it to get a relief from both mental and physical stress they go through whole day because alcohol is one kind of stress buster.


Nevertheless,ironically, all of them know that hooch is dangerous for health, and in past it has taken lots of lives, despite the knowledge of reality they consume it, just for relaxation from the stress they recieve.



Selling hooch is illegal and officially it's not banned.


The ultimate truth is that  it plays a major role in black economy and these hooch dealers have their own hooch dens even in the heart of metro cities, because these hooch dens provide nice money both to local politicians and police, so they don't care, because this poison kills poor people, not the rich.


Who does cares for the  poor people?


The state,law and order,the democracy,the politics and even the religion,none seems to be responsible for the tragedy of the victims.


It is understood that the  government as well as the administration may take serious steps anytime,anywhere against these hooch dealers but they don't because they do need support of local politicians to reclaim power and they don't want to close the shutters on the infinite flow of their unlimited nontaxable(local politicians) income.


And for the government poor people don't exist but government need its hooligans to maintain its regime,because hooligans play role in voting procedure.


In Indian democracy, not the poor, but these hooligans are the most creative men power in one way or other,deeply involved in this business do decide to decide the mandate to run and rule the white economy with black power and muscles.


Thus,the majority population would still consume this poison.


They don't want to know the complexity and at the same time, they don't care because they know they can't change it.


They would consume the poison because it relaxes them from daily stress and comes according to their budget .


I asked a guy once,"why you drink this poison it will kill you", he replied ,"the system has murdered us so we are already dead.".



Alcohol

From Wikipedia, the free encyclopedia

This article is about the class of chemical compounds. For beverages containing these compounds, see Alcoholic beverage. For other uses, see Alcohol (disambiguation).

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Ball-and-stick model of the hydroxyl (-OH) functional group in an alcohol molecule (R3COH). The three "R's" stand for carbon substituents or hydrogen atoms.[1]

The hydroxyl (-OH) functional group with bond angle

In chemistry, an alcohol is an organic compound in which the hydroxyl functional group (-OH) is bound to a carbon atom. In particular, this carbon center should be saturated, having single bonds to three other atoms.[2]

In alcohol cultures, the term alcohol originally refereed to the primary alcohol ethyl alcohol(ethanol), the dominating alcohol in alcoholic beverages. However, since then, other alcohols have been identified, including the secondary alcohol isopropanol, and the tertiary alcohol tert-Amyl alcohol. Nowadays, the term alcohol in this context instead refers to the alcohol as a drug family (chemical class).

The suffix -ol appears in the IUPAC chemical name of all substances where the hydroxyl group is the functional group with the highest priority; in substances where a higher priority group is present the prefix hydroxy- will appear in the IUPAC name. 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. An important class of alcohols are the simpleacyclic alcohols, the general formula for which is CnH2n+1OH.

Contents

 [hide]

Occurrence in nature

See also: Ethanol § Human metabolite and Methanol § Human metabolite

[icon]

This section requires expansion.(June 2014)

Alcohol has been found outside the Solar System. It can be found in low densities in star and planetary-system-forming regions of space.[3][non-primary source needed][better source needed]

Toxicity

This section needs more medical references for verification or relies too heavily on primary sources. Please review the contents of the section and add the appropriate references if you can. Unsourced or poorly sourced material may be removed. (June 2014)

Rod of Asclepius2.svg


This section needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (June 2014)

Ball-and-stick model of tert-Amyl alcohol, which is 20 times more intoxicating than ethanol and like all tertiary alcohols, cannot be metabolised to toxic aldehydes.[4][5][better source needed][6][better source needed]

Most significant of the possiblelong-term effects of ethanol. In addition, in pregnant women, it causes fetal alcohol syndrome.

Ethanol's toxicity is largely caused by its primary metabolite, acetaldehyde(systematically ethanal)[7][better source needed][8][better source needed] and secondary metabolite, acetic acid.[8][9][10][11] All primary alcohols are broken down into aldehydes then to carboxylic acids whose toxicities are similar to acetaldehyde and acetic acid.[citation needed] Metabolite toxicity is reduced in rats fed N-acetylcysteine[7][12] and thiamine.[13]

Tertiary alcohols cannot be metabolized into aldehydes[14] and as a result they cause no hangover or toxicity through this mechanism.

Some secondary and tertiary alcohols are less poisonous than ethanol because the liver is unable to metabolize them into toxic by-products.[15] This makes them more suitable for recreational[16][17] and medicinal[18] use as the chronic harms are lower.Ethchlorvynol and tert-Amyl alcohol are good examples of tertiary alcohols which saw both medicinal and recreational use.[19]

Other alcohols are substantially more poisonous than ethanol, partly because they take much longer to be metabolized and partly because their metabolism produces substances that are even more toxic. Methanol (wood alcohol), for instance, is oxidized to formaldehyde and then to the poisonous formic acid in the liver byalcohol dehydrogenase and formaldehyde dehydrogenase enzymes, respectively; accumulation of formic acid can lead to blindness or death.[20] Likewise, poisoning due to other alcohols such as ethylene glycol or diethylene glycol are due to their metabolites, which are also produced by alcohol dehydrogenase.[21][22]

Methanol itself, while poisonous (LD50 5628 mg/kg, oral, rat[23]), has a much weakersedative effect than ethanol.

Isopropyl alcohol is oxidized to form acetone by alcohol dehydrogenase in the liver but has occasionally been abused by alcoholics, leading to a range of adverse health effects.[24][better source needed][25][better source needed]

Treatment

An effective treatment to prevent toxicity after methanol or ethylene glycol ingestion is to administer ethanol. Alcohol dehydrogenase has a higher affinity for ethanol, thus preventing methanol from binding and acting as a substrate. Any remaining methanol will then have time to be excreted through the kidneys.[20][26][27]

Nomenclature

Systematic names

IUPAC nomenclature is used in scientific publications and where precise identification of the substance is important, especially in cases where the relative complexity of the molecule does not make such a systematic name unwieldy. In the IUPAC system, in naming simple alcohols, the name of the alkane chain loses the terminal "e" and adds "ol", e.g., as in "methanol" and "ethanol".[28] When necessary, the position of the hydroxyl group is indicated by a number between the alkane name and the "ol": propan-1-ol for CH3CH2CH2OH, propan-2-ol for CH3CH(OH)CH3. If a higher priority group is present (such as an aldehyde, ketone, or carboxylic acid), then the prefix "hydroxy" is used,[28] e.g., as in 1-hydroxy-2-propanone (CH3C(O)CH2OH).[29]

Some examples of simple alcohols and how to name them


Common names

In other less formal contexts, an alcohol is often called with the name of the corresponding alkyl group followed by the word "alcohol", e.g., methyl alcohol, ethyl alcohol. Propyl alcohol may be n-propyl alcohol or isopropyl alcohol, depending on whether the hydroxyl group is bonded to the end or middle carbon on the straight propane chain. As described under systematic naming, if another group on the molecule takes priority, the alcohol moiety is often indicated using the "hydroxy-" prefix.

Alcohols are then classified into primary, secondary (sec-, s-), and tertiary (tert-, t-), based upon the number of carbon atoms connected to the carbon atom that bears the hydroxyl functional group. (The respective numeric shorthands 1°, 2°, and 3° are also sometimes used in informal settings.[citation needed]) The primary alcohols have general formulas RCH2OH; methanol (CH3OH is the simplest primary alcohol (R=H), and after it, ethanol (R=CH3). Secondary alcohols can be referred to with the shorthand RR'CHOH; 2-propanol is the simplest example (R=R'=CH3). Tertiary alcohols can be referred to with the shorthand RR'R"COH; tert-butanol (2-methylpropan-2-ol) is the simplest example (R=R'=R"=CH3). In these shorthands, R, R', and R" represent substituents, alkyl or other attached, generally organic groups.

Chemical Formula

IUPAC Name

Common Name

Monohydric alcohols



CH3OH

Methanol

Wood alcohol

C2H5OH

Ethanol

Alcohol

C3H7OH

Isopropyl alcohol

Rubbing alcohol

C4H9OH

Butyl alcohol

Butanol

C5H11OH

Pentanol

Amyl alcohol

C16H33OH

Hexadecan-1-ol

Cetyl alcohol

Polyhydric alcohols



C2H4(OH)2

Ethane-1,2-diol

Ethylene glycol

C3H6(OH)2

Propane-1,2-diol

Propylene Glycol

C3H5(OH)3

Propane-1,2,3-triol

Glycerol

C4H6(OH)4

Butane-1,2,3,4-tetraol

Erythritol, Threitol

C5H7(OH)5

Pentane-1,2,3,4,5-pentol

Xylitol

C6H8(OH)6

Hexane-1,2,3,4,5,6-hexol

Mannitol, Sorbitol

C7H9(OH)7

Heptane-1,2,3,4,5,6,7-heptol

Volemitol

Unsaturated aliphatic alcohols



C3H5OH

Prop-2-ene-1-ol

Allyl alcohol

C10H17OH

3,7-Dimethylocta-2,6-dien-1-ol

Geraniol

C3H3OH

Prop-2-in-1-ol

Propargyl alcohol

Alicyclic alcohols



C6H6(OH)6

Cyclohexane-1,2,3,4,5,6-hexol

Inositol

C10H19OH

2 - (2-propyl)-5-methyl-cyclohexane-1-ol

Menthol

Alkyl chain variations in alcohols

Short-chain alcohols have alkyl chains of 1-3 carbons. Medium-chain alcohols have alkyl chains of 4-7 carbons. Long-chain alcohols (also known as fatty alcohols) have alkyl chains of 8-21 carbons, and very long-chain alcohols have alkyl chains of 22 carbons or longer.[30]

Simple alcohols

"Simple alcohols" appears to be a completely undefined term. However, simple alcohols are often referred to by common names derived by adding the word "alcohol" to the name of the appropriate alkyl group. For instance, a chain consisting of one carbon (a methyl group, CH3) with an OH group attached to the carbon is called "methyl alcohol" while a chain of two carbons (an ethyl group, CH2CH3) with an OH group connected to the CH2 is called "ethyl alcohol." For more complex alcohols, the IUPAC nomenclature must be used.[31]

Simple alcohols, in particular ethanol and methanol, possess denaturing and inert rendering properties, leading to their use as anti-microbial agents in medicine, pharmacy, and industry.[citation needed]

Higher alcohols

Encyclopædia Britannica states, "The higher alcohols - those containing 4 to 10 carbon atoms – are somewhat viscous, or oily, and they have heavier fruity odours. Some of the highly branched alcohols and many alcohols containing more than 12 carbon atoms are solids at room temperature."[32]

Like ethanol, butanol can be produced by fermentation processes. (However, the fermenting agent is a bacterium,Clostridium acetobutylicum, that feeds on cellulose, not sugars like the Saccharomyces yeast that produces ethanol.) Saccharomyces yeast are known to produce these higher alcohols at temperatures above 75 °F (24 °C).

History and etymology

The word alcohol appears in English as a term for a very fine powder in the 16th century. It was borrowed from French, which took it from medical Latin.

Ultimately the word is from the Arabic كحل (al-kuḥl, "kohl, a powder used as an eyeliner"). Al- is the Arabic definitive article, equivalent to the in English; alcohol was originally used for the very fine powder produced by the sublimation of the natural mineral stibnite to form antimony sulfide Sb2S3 (hence the essence or "spirit" of the substance), which was used as anantiseptic, eyeliner, and cosmetic (see kohl (cosmetics)). Bartholomew Traheron, in his 1543 translation of John of Vigo, introduces the word as a term used by "barbarous" (Moorish) authors for "fine powder." Vigo wrote: the barbarous auctours use alcohol, or (as I fynde it sometymes wryten) alcofoll, for moost fine poudre.

The 1657 Lexicon Chymicum by William Johnson glosses the word as antimonium sive stibium. By extension, the word came to refer to any fluid obtained by distillation, including "alcohol of wine," the distilled essence of wine. Libavius inAlchymia (1594) refers to vini alcohol vel vinum alcalisatum. Johnson (1657) glosses alcohol vini as quando omnis superfluitas vini a vino separatur, ita ut accensum ardeat donec totum consumatur, nihilque fæcum aut phlegmatis in fundo remaneat. The word's meaning became restricted to "spirit of wine" (the chemical known today as ethanol) in the 18th century and was extended to the class of substances so-called as "alcohols" in modern chemistry after 1850.

The first alcohol (today known as ethyl alcohol) was discovered by the tenth-century Persian alchemist Muhammad ibn Zakariya al-Razi. The current Arabic name for alcohol (ethanol) is الغول al-ġawl – properly meaning "spirit" or "demon" – with the sense "the thing that gives the wine its headiness" (in the Qur'an sura 37 verse 47).[33] The term ethanol was invented 1838, modeled on the German word äthyl (Liebig), which is in turn based on Greek aither ether and hyle "stuff."[34]

Physical and chemical properties

Alcohols have an odor that is often described as "biting" and as "hanging" in the nasal passages. Ethanol has a slightly sweeter (or more fruit-like) odor than the other alcohols.

In general, the hydroxyl group makes the alcohol molecule polar. Those groups can form hydrogen bonds to one another and to other compounds (except in certain large molecules where the hydroxyl is protected by steric hindrance of adjacent groups[35]). This hydrogen bonding means that alcohols can be used as protic solvents. Two opposing solubility trends in alcohols are: the tendency of the polar OH to promote solubility in water, and the tendency of the carbon chain to resist it. Thus, methanol, ethanol, and propanol are miscible in water because the hydroxyl group wins out over the short carbon chain. Butanol, with a four-carbon chain, is moderately soluble because of a balance between the two trends. Alcohols of five or more carbons (pentanol and higher) are effectively insoluble in water because of the hydrocarbon chain's dominance. All simple alcohols are miscible in organic solvents.

Because of hydrogen bonding, alcohols tend to have higher boiling points than comparable hydrocarbons and ethers. The boiling point of the alcohol ethanol is 78.29 °C, compared to 69 °C for the hydrocarbon hexane (a common constituent ofgasoline), and 34.6 °C for diethyl ether.

Alcohols, like water, can show either acidic or basic properties at the -OH group. With a pKa of around 16-19, they are, in general, slightly weaker acids than water, but they are still able to react with strong bases such as sodium hydride or reactive metals such as sodium. The salts that result are called alkoxides, with the general formula RO- M+.

Meanwhile, the oxygen atom has lone pairs of nonbonded electrons that render it weakly basic in the presence of strong acids such as sulfuric acid. For example, with methanol:

Acidity & basicity of methanol

Alcohols can also undergo oxidation to give aldehydes, ketones, or carboxylic acids, or they can be dehydrated to alkenes. They can react to form ester compounds, and they can (if activated first) undergo nucleophilic substitution reactions. The lone pairs of electrons on the oxygen of the hydroxyl group also makes alcohols nucleophiles. For more details, see thereactions of alcohols section below.

As one moves from primary to secondary to tertiary alcohols with the same backbone, the hydrogen bond strength, the boiling point, and the acidity typically decrease.

Applications

Total recorded alcohol per capita consumption (15+), in litres of pure alcohol[36]

Alcohol has a long history of several uses worldwide. It is found in alcoholic beverages sold to adults, as fuel, and also has many scientific, medical, and industrial uses. The term alcohol-free is often used to describe a product that does not contain alcohol. Some consumers of some commercially prepared products may view alcohol as an undesirable ingredient, particularly in products intended for children.

Alcoholic beverages

Alcoholic beverages, typically containing 3–40% ethanol by volume, have been produced and consumed by humans since pre-historic times. Other alcohols such as 2-methyl-2-butanol (found in beer) and γ-hydroxybutyric acid are also consumed by humans for their psychoactive effects.

Antifreeze

A 50% v/v (by volume) solution of ethylene glycol in water is commonly used as an antifreeze.

Antiseptics

Ethanol can be used as an antiseptic to disinfect the skin before injections are given, often along with iodine. Ethanol-basedsoaps are becoming common in restaurants and are convenient because they do not require drying due to the volatility of the compound. Alcohol based gels have become common as hand sanitizers.

Fuels

Some alcohols, mainly ethanol and methanol, can be used as an alcohol fuel. Fuel performance can be increased in forced induction internal combustion engines by injecting alcohol into the air intake after the turbocharger or supercharger has pressurized the air. This cools the pressurized air, providing a denser air charge, which allows for more fuel, and therefore more power.

Preservative

Alcohol is often used as a preservative for specimens in the fields of science and medicine.

Solvents

Hydroxyl groups (-OH), found in alcohols, are polar and therefore hydrophilic (water loving) but their carbon chain portion isnon-polar which make them hydrophobic. The molecule increasingly becomes overall more nonpolar and therefore less soluble in the polar water as the carbon chain becomes longer.[37] Methanol has the shortest carbon chain of all alcohols (one carbon atom) followed by ethanol (two carbon atoms.)

Alcohols have applications in industry and science as reagents or solvents. Because of its relatively low toxicity compared with other alcohols and ability to dissolve non-polar substances, ethanol can be used as a solvent in medical drugs,perfumes, and vegetable essences such as vanilla. In organic synthesis, alcohols serve as versatile intermediates.

Production

Ziegler and Oxo Processes

In the Ziegler process, linear alcohols are produced from ethylene and triethylaluminium followed by oxidation and hydrolysis.[38] An idealized synthesis of 1-octanol is shown:

Al(C2H5)3 + 9 C2H4 → Al(C8H17)3

Al(C8H17)3 + 3 O + 3 H2O → 3 HOC8H17 + Al(OH)3

The process generates a range of alcohols that are separated by distillation.

Many higher alcohols are produced by hydroformylation of alkenes followed by hydrogenation. When applied to a terminal alkene, as is common, one typically obtains a linear alcohol:[38]

RCH=CH2 + H2 + CO → RCH2CH2CHO

RCH2CH2CHO + 3 H2 → RCH2CH2CH2OH

Such processes give fatty alcohols, which are useful for detergents.

Hydration reactions

Low molecular weight alcohols of industrial importance are produced by the addition of water to alkenes. Ethanol, isopropanol, 2-butanol, and tert-butanol are produced by this general method. Two implementations are employed, the direct and indirect methods. The direct method avoids the formation of stable intermediates, typically using acid catalysts. In the indirect method, the alkene is converted to the sulfate ester, which is subsequently hydrolyzed. The direct hydrationusing ethylene (ethylene hydration)[39] or other alkenes from cracking of fractions of distilled crude oil.

Hydration is also used industrially to produce the diol ethylene glycol from ethylene oxide.

Biological routes

Ethanol is obtained by fermentation using glucose produced from sugar from the hydrolysis of starch, in the presence of yeast and temperature of less than 37 °C to produce ethanol. For instance, such a process might proceed by the conversion of sucrose by the enzyme invertase into glucose and fructose, then the conversion of glucose by the enzymezymase into ethanol (and carbon dioxide).

Several of the benign bacteria[which?] in the intestine use fermentation as a form of anaerobic metabolism. This metabolicreaction produces ethanol as a waste product, just like aerobic respiration produces carbon dioxide and water. Thus, human bodies contain some quantity of alcohol endogenously produced by these bacteria. In rare cases, this can be sufficient to cause "auto-brewery syndrome" in which intoxicating quantities of alcohol are produced.[40][41][42]

Laboratory synthesis

Several methods exist for the preparation of alcohols in the laboratory.

Substitution

Primary alkyl halides react with aqueous NaOH or KOH mainly to primary alcohols in nucleophilic aliphatic substitution. (Secondary and especially tertiary alkyl halides will give the elimination (alkene) product instead). Grignard reagents react with carbonyl groups to secondary and tertiary alcohols. Related reactions are the Barbier reaction and the Nozaki-Hiyama reaction.

Reduction

Aldehydes or ketones are reduced with sodium borohydride or lithium aluminium hydride (after an acidic workup). Another reduction by aluminiumisopropylates is the Meerwein-Ponndorf-Verley reduction. Noyori asymmetric hydrogenation is the asymmetric reduction of β-keto-esters.

Hydrolysis

Alkenes engage in an acid catalysed hydration reaction using concentrated sulfuric acid as a catalyst that gives usually secondary or tertiary alcohols. The hydroboration-oxidation and oxymercuration-reduction of alkenes are more reliable in organic synthesis. Alkenes react with NBS and water in halohydrin formation reaction. Amines can be converted todiazonium salts, which are then hydrolyzed.

The formation of a secondary alcohol via reduction and hydration is shown:

Preparation of a secondary alcohol

Reactions

Deprotonation

Alcohols can behave as weak acids, undergoing deprotonation. The deprotonation reaction to produce an alkoxide salt is performed either with a strong base such as sodium hydride or n-butyllithium or with sodium or potassium metal.

2 R-OH + 2 NaH → 2 R-O-Na+ + 2H2

2 R-OH + 2 Na → 2 R-ONa+ + H2

2 CH3CH2-OH + 2 Na → 2 CH3-CH2-O-Na+ + H2

Water is similar in pKa to many alcohols, so with sodium hydroxide there is an equilibrium set-up, which usually lies to the left:

R-OH + NaOH ⇌ R-O-Na+ + H2O (equilibrium to the left)

It should be noted, however, that the bases used to deprotonate alcohols are strong themselves. The bases used and the alkoxides created are both highly moisture-sensitive chemical reagents.

The acidity of alcohols is also affected by the overall stability of the alkoxide ion. Electron-withdrawing groups attached to the carbon containing the hydroxyl group will serve to stabilize the alkoxide when formed, thus resulting in greater acidity. On the other hand, the presence of electron-donating group will result in a less stable alkoxide ion formed. This will result in a scenario whereby the unstable alkoxide ion formed will tend to accept a proton to reform the original alcohol.

With alkyl halides alkoxides give rise to ethers in the Williamson ether synthesis.

Nucleophilic substitution

The OH group is not a good leaving group in nucleophilic substitution reactions, so neutral alcohols do not react in such reactions. However, if the oxygen is first protonated to give R−OH2+, the leaving group (water) is much more stable, and the nucleophilic substitution can take place. For instance, tertiary alcohols react with hydrochloric acid to produce tertiary alkyl halides, where the hydroxyl group is replaced by a chlorine atom by unimolecular nucleophilic substitution. If primary or secondary alcohols are to be reacted with hydrochloric acid, an activator such as zinc chloride is needed. In alternative fashion, the conversion may be performed directly using thionyl chloride.[1]

Some simple conversions of alcohols to alkyl chlorides

Alcohols may, likewise, be converted to alkyl bromides using hydrobromic acid or phosphorus tribromide, for example:

3 R-OH + PBr3 → 3 RBr + H3PO3

In the Barton-McCombie deoxygenation an alcohol is deoxygenated to an alkane with tributyltin hydride or a trimethylborane-water complex in a radical substitution reaction.

Dehydration

Alcohols are themselves nucleophilic, so R−OH2+ can react with ROH to produce ethers and water in a dehydration reaction, although this reaction is rarely used except in the manufacture of diethyl ether.

More useful is the E1 elimination reaction of alcohols to produce alkenes. The reaction, in general, obeys Zaitsev's Rule, which states that the most stable (usually the most substituted) alkene is formed. Tertiary alcohols eliminate easily at just above room temperature, but primary alcohols require a higher temperature.

This is a diagram of acid catalysed dehydration of ethanol to produce ethene:

DehydrationOfAlcoholWithH-.png

A more controlled elimination reaction is the Chugaev elimination with carbon disulfide and iodomethane.

Esterification

To form an ester from an alcohol and a carboxylic acid the reaction, known as Fischer esterification, is usually performed atreflux with a catalyst of concentrated sulfuric acid:

R-OH + R'-COOH → R'-COOR + H2O

In order to drive the equilibrium to the right and produce a good yield of ester, water is usually removed, either by an excess of H2SO4 or by using a Dean-Stark apparatus. Esters may also be prepared by reaction of the alcohol with an acid chloridein the presence of a base such as pyridine.

Other types of ester are prepared in a similar manner – for example, tosyl (tosylate) esters are made by reaction of the alcohol with p-toluenesulfonyl chloride in pyridine.

Oxidation

Main article: Alcohol oxidation

Primary alcohols (R-CH2-OH) can be oxidized either to aldehydes (R-CHO) or to carboxylic acids (R-CO2H), while the oxidation of secondary alcohols (R1R2CH-OH) normally terminates at the ketone (R1R2C=O) stage. Tertiary alcohols (R1R2R3C-OH) are resistant to oxidation.

The direct oxidation of primary alcohols to carboxylic acids normally proceeds via the corresponding aldehyde, which is transformed via an aldehyde hydrate (R-CH(OH)2) by reaction with water before it can be further oxidized to the carboxylic acid.

Mechanism of oxidation of primary alcohols to carboxylic acids via aldehydes and aldehyde hydrates

Reagents useful for the transformation of primary alcohols to aldehydes are normally also suitable for the oxidation of secondary alcohols to ketones. These include Collins reagent and Dess-Martin periodinane. The direct oxidation of primary alcohols to carboxylic acids can be carried out using potassium permanganate or the Jones reagent.

See also

Notes

References

  • Metcalf, Allan A. (1999). The World in So Many Words. Houghton Mifflin. ISBN 0-395-95920-9.

External links

Look up alcohol in Wiktionary, the free dictionary.


Wikimedia Commons has media related to Alcohol.


Wikiquote has a collection of quotations related to: Alcohol


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Alcohols






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  3. Bengal hooch tragedy: Death toll rises to 143 - NDTV

    www.ndtv.com › All India
    Dec 15, 2011 - ... in what is one of West Bengal's worst hooch tragedies has gone up to 143. ... When we try take action to stop this business, resistance comes ...
  4. Bengal hooch tragedy: Death toll rises to 143; over 350 still ...

    www.ndtv.com › All India
    Dec 15, 2011 - In one home after another in West Bengal's Sangrampur and ... and said, "Illegal liquor business has been taking place for long in the state.
  5. Hooch tragedy in Bengal: Booze business and statistics ...

    timesofindia.indiatimes.com/.../Hooch...Bengal...business.../11127955.c...
    Dec 16, 2011 - The Country liquor (CL) market was estimated at 220 million cases (of 9 litres each) in 2008 with a retail value of Rs 25000 crore.
  6. Bengal youth killed by hooch mafia, one arrested - The ...

    timesofindia.indiatimes.com › City
    Jul 7, 2014 - Bengal youth killed by hooch mafia, one arrested. The author has posted ..... So no wMamta has got this side business to perform. Good for the ...
  7. Hooch Tragedy: Latest News on Hooch Tragedy, Read ...

    ibnlive.in.com/newstopics/hooch-tragedy.html
    Mamata calls meet over West Bengal hooch tragedy 23-12-2011 08:41 AM .... Tragic deaths apart, hooch business goes on in Guj 12-07-2009 03:56 PM.
  8. West Bengal hooch tragedy: 86 dead, 4 arrested - IBNLive

    ibnlive.in.com › Business
    In one of the worst hooch tragedies in the recent times in West Bengal, ... 9 hours 28 minutes ago; Reliance Power to buy Jaiprakash's hydropower business 11 ...
  9. West Bengal Hooch Tragedy - Zee News - India

    zeenews.india.com/photogallery/west-bengal-hooch-tragedy-2142
    West Bengal Hooch Tragedy. active. Previous Next ... 1998-2014 Zee Media Corporation Ltd (An Essel Group Company), All rights reserved. Contact | Privacy ...
  10. Bengal hooch tragedy: 4 held | Business Line

    www.thehindubusinessline.com/.../bengal-hooch...4.../article2747388.ec...
    Dec 25, 2011 - Four persons, including the wife of the main accused Noor Islam Sheikh alias 'Khora' Badshah, were held early today by a CID team in ...

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