# Tag Info

47

Nope. Alcohols consist of an $\ce{OH}$ group bonded to a saturated carbon ($sp^3$ hybridized, no multiple bonds) IUPAC says: alcohols Compounds in which a hydroxy group, $\ce{–OH}$, is attached to a saturated carbon atom $\ce{R3COH}$. The term 'hydroxyl' refers to the radical species, $\ce{HO.}$. and phenols Compounds having one or more ...

30

Technically, alcohol is the name of a class of organic compounds containing one or several hydroxyl groups. Colloquially, the term "alcohol" is understood as you have described: A solution (of varying degree of purity) of ethanol and water. Pure ethanol is impossible to create via the traditional method of purification (atmospheric distillation) as the ...

23

In the conversion of primary alcohols to primary amines $$\ce{R-CH2OH -> R-CH2NH2}$$ direct alkylation of ammonia normally is the last thing you want to do in the lab. Under conditions where $\ce{OH}$ is a good leaving group, i.e. in acidic medium, the nucleophilicity of ammonia is reduced due to protonation. Moreover, there's little chance to prevent ...

20

(I'm no chemist, but here's my take on it) Let's see: I’m an alcoholic, and I really hate having to dole out large amounts of cash to purchase your usual "drinking"-ethanol. So I get this amazing idea to separate the ethanol by distillation (methanol has a lower boiling point than methanol, so what I'll really be doing is distilling out the methanol, ...

19

In the pinacol rearrangement, a 1,2-diol is treated with acid and rearranges to a carbonyl compound. Here is a reaction scheme showing a mechanism for the rearrangement. In this case the molecule is symmetric and methyl migration is the only reaction pathway available. Methyl migration can 1) help stabilize the developing carbocation center and 2) once ...

18

The function of pyridine is actually not so simple and not so easy to notice at first glance. There is a fundamental reason why pyridine is used to promote the acylation reaction, which is that it can act as a catalyst. Despite its basicity and the subsequent formation of its chlorhydrate salt after the tosylation reaction, pyridine is also an excellent ...

18

You are both right and wrong. At low temperatures, the NMR spectrum will indeed be as you predicted: the $\ce{H}$ from $\ce{OH}$ will produce a quartet and likewise the $\ce{H}$ from $\ce{CH_3}$ will produce a doublet. Note that at low temperatures the formation of $\ce{H}$ bonds is favored, hence leading to more stable components and significantly ...

17

The golden book states that ethenol is an alcohol: Enols Alkenols; the term refers specifically to vinylic alcohols, which have the structure $\ce{HOCR'=CR2}$. However, the modifier "vinylic" is rather important, so I would never omit it.

15

Thionyl chloride is preferred for preparing alkyl chlorides from alcohols because the by-products formed in the reaction are $\ce{SO2}$ and $\ce{HCl}$ which are in gaseous form and escape into the atmosphere leaving behind pure alkyl chlorides. $$\ce{CH3CH2-OH + SOCl2 → CH3CH2-Cl + SO2 ↑ + HCl ↑}$$

15

Preparation of alkyl chlorides from alcohols by thionyl chloride is preferred over other methods mentioned because of the following reasons : $$\ce{R-OH + PCl5 → R-Cl + POCl3 + HCl ↑}$$ $$\ce{3R-OH + PCl3 → 3R-Cl + H3PO3}$$ $$\ce{R-OH + SOCl2 → R-Cl + SO2 ↑ + HCl ↑}$$ Both the byproducts formed in the last reaction i.e., $\ce{SO2}$ and ...

14

Litmus is a weak acid, with a $\mathrm{p}K_\mathrm{a}$ of about 6.5. Alcohols are extremely weak acids, with $\mathrm{p}K_\mathrm{a}$'s (typically) around 17. The litmus itself is a much stronger acid than the alcohol. Dissociation of the alcohol won't produce enough protons to shift the equilibrium between the two colored forms of the indicator, so you'...

14

Generally speaking, they're called diols when bearing two hydroxyl groups. If they're on the same C, this is called a geminal diol, if they are on neighboring Cs, they're called vicinal diols. The C on geminal diols has a higher oxidation state than that of an alcohol, i.e. which is why they could be seen as relatives of an aldehydes (or ketones). In a ...

12

This article on Wikipedia says your compound, ethyl sulphate, can be synthesized, by adding sulfuric acid drop-wise to boiling ethanol and temperature should be kept below 413K which agrees with your data. I found also an article according to which authors conducted esterification at about 300K, but with starting presence of anhydrous sodium sulfate. Also ...

12

You have managed to draw the correct acyclic hydrolized compound with a decent mechanism. This is a problem that can be solved by numbering the carbon atoms. Number the carbon atoms sequentially along the chain, starting with the acetal carbon (which has to be the carbonyl group). Likewise number the unpacked acyclic molecule. Use what you get to figure ...

11

The first reaction is the conversion of the alcohol to an alkyl chloride using thionyl chloride. The mechanism of the reaction starts with nucleophilic attack of the alcohol oxygen on sulphur, followed by displacement of $\ce{Cl-}$. Chloride then substitutes the alkyl chlorosulfite group in an $\ce{S_{N}2}$ reaction, and the latter decomposes into $\ce{SO2}$ ...

11

Tschoppi’s answer is technically correct, since it is nigh impossible to create a pure compound without any contaminants. The highest-grade liquids I can remember seeing on SigmaAldrich’s web pages were something like $99.9999~\%$ purity or something — far enough away from $100~\%$ to call it a solution. However in practice, chemists (especially non-...

11

The strength of a hydrogen bond somewhat depends on the $\ce{X-H\bond{...}X}$ angle that the hydrogen-bonding hydrogen forms with the two electronegative elements $\ce{X}$. In our case, carboxylic acids or alcohols, $\ce{X} = \ce{O}$ so the angle is $\ce{O-H\bond{...}O}$. The ideal angle for this fragment is $180^\circ$. As you have drawn for carboxylic ...

10

Cyclodextrins, which comprise a class of cyclic carbohydrates, use their properties of being hydrophobic within their ring(s), yet hydrophilic outside. Alcohol can be put inside these rings. Then, the entire molecule is still capable of dissolving in water, releasing the encapsulated alcohol molecules. (src) This popsci link has one way of making edible ...

10

Secondary and tertiary alcohols react with strong acid (and bases) such $\ce{HX}$ following SN1 mechanism. $$\ce{ROH <=> HX + ROH_2^+ + X^-} \tag{1}$$ $$\ce{ROH_2^+ <=> R^+ +H_2O} \tag{2}$$ $$\ce{R+ +X- \rightarrow RX} \tag{3}$$ In these reactions, the rate determining step is the formation of the carbocation (2). So the successive attack of ...

10

You can view water as the simplest alcohol, and indeed, water reacts with all of the Group 1 metals to form hydrogen gas and the corresponding metal hydroxide according to the following equation $\ce{2M + 2HOH -> 2MOH + H2}$ where $\ce{M}$ is the metal. The same reaction occurs with simple alcohols to produce the corresponding metal alkoxide and ...

10

Remember your general chemistry. In an acid-base reaction, the equilibrium favors the side of the reaction with the weaker acid/base pair. Strong bases have weak conjugate acids. Strong acids have weak conjugate bases. Weak bases have strong conjugate acids. Weak acids have strong conjugate bases. Consider the following: $$\ce{HA + B- <=> A- + HB}$$ ...

10

First, water's $\ce{pK_a}$ in water is $\ce{14}$ as explained here. This means that $\ce{H2O}$ is slightly dissociated in liquid form, such that $\ce{[H+] = [HO-] = 10^{-7}}$. Second, I would say that caring too much about which compound is the best acid is a bit like arguing by definition. Acidity is a fuzzy concept used as a shorthand for deeper meaning. ...

10

The reason criminals don't undenture alcohol is probably because it's cheap and easy to make your own alcohol at home. Plus it's legal in the US (click on G1) and most other English-speaking countries. You can get equipment kits from anywhere between 50 and 200 USD (more expensive kits will get you tools that make things easier or improve quality and add ...

10

In Soviet Russia, where alcoholism was widespread and homebrewing illegal, undenaturing alcohol was a pretty common thing - a part of national culture, in a way - along with such practices as: drinking straight down various non-food grade products containing ethanol or extracting ethanol from them or stealing ethanol from industrial processes or, well, ...

10

Strange as it may seem, benzene can be reacted with steam over a suitable catalyst [1]. The result is a complete breakdown to simpler molecules like methane and carbon dioxide. Typical conditions are 0.055 atm partial pressure benzene, 0.60 atm partial pressure steam, and 370 °C temperature. The cited reference also considers the breakdown of ...

9

Let me answer the second question first, because the answer is so much easier: Of course the hydrogen bond strength depends among others upon the carbon oxygen is attached to. Consider phenol and methanol or methanol and formic acid. The guess as to which hydrogen bond is stronger is — I have to admit it — my speculation. But I think that methanol should be ...

9

General considerations It’s not the basicity that is the important factor here, it is the nucleophilicity. The hydride ion, whether present as tetrahydridoborate or as a lone hydride is a very lousy nucleophile while an alcohol is an okay-ish nucleophile. The general mechanism of the addition is given in scheme 1. Scheme 1: General mechanism of a ...

9

I think it is possible to use hydrogen peroxide. This paper discusses it: http://greenchem.uoregon.edu/PDFs/ResourceID88.pdf Other alternatives: Pyridinium Chlorochromate (or PCC for short) Dess-Martin Reagent Swern Oxidation: oxalyl chloride in DMSO with triethyl amine Fétizon Oxidation: silver(I) carbonate absorbed onto the surface of celite (Fétizon's ...

9

Background You don't specify whether we are starting with cis- or trans-cyclohexane-1,2-diol, but it doesn't matter since both isomers will interconvert under the reaction conditions. Therefore we will need to consider the reaction products from both isomers. These reactions run in strong acid are never clean. I'd bet that some cyclohexanone was also ...

9

The addition of Grignards to propargyl alcohols occurs via the alkoxide salt, after deprotonation:[1] Here: the reactivity may be explained by the stabilising influence of complexation; the regioselectivity may be explained by the preference of a five-membered chelate ring over a four-membered one; and the stereoselectivity arises because syn addition ...

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