Benzyl alcohol , or phenylmethanol, is used in perfumes, flavors, soaps, cosmetics, ointments, and ball point pen inks; it is also used in some anti-itching medications.
Cinnamic alcohol 3D Download 3D Cinnamic alcohol , or cinnamyl alcohol, is found in cinnamon leaves hence the name , usually in the form of an ester; it is also found in Tolu balsam, the resin of the Myroxylon toluifera tree.
It has an odor similar to that of hyacinth, and is used in perfumes particularly in lilac and other floral scents , deodorants, flavoring agent, soaps, and cosmetics. Diethylene glycol 3D Download 3D Diethylene glycol DEG is a colorless, odorless, toxic liquid used as an industrial solvent, and in the synthesis of other organic molecules.
It is also used as a humectant for tobacco, and some inks and glues. In , the S. Massengill Co. Several other cases of DEG poisoning have resulted from DEG either being added to wines in an attempt to sweeten them, or because of its presence in improperly purified medications and cosmetics.
In May of , several cheap brands of toothpaste originating in China were removed from the market in several countries because they were found to be contaminated with DEG labeled on the containers as "glycerine". It is used in a insecticide called grandlure , which attracts and traps or kills these damaging insects. Cyclohexanol 3D Download 3D Cyclohexanol is a cyclic, secondary alcohol.
It is used in some organic synthesis reactions, in the manufacture of celluloid, textiles, and some insecticides. Garden City: Anchor Books, , p. Atkins, Molecules , 2nd ed. Cambridge: Cambridge University Press, , p. Richard J. Lewis, Sr. New York: Van Nostrand Reinhold, Sharp, The Penguin Dictionary of Chemistry , 2nd ed. London: Penguin Books, Martha Windholz ed. Methanol 3D Download 3D Methanol , also known as methyl alcohol and wood alcohol , is the simplest of the alcohols.
Download 3D Benzyl alcohol 3D Download 3D Benzyl alcohol , or phenylmethanol, is used in perfumes, flavors, soaps, cosmetics, ointments, and ball point pen inks; it is also used in some anti-itching medications.
Navigation Bar. Molecule Gallery. Download 3D. Ethanol , also known as ethyl alcohol and grain alcohol , is the alcohol found in alcoholic beverages. Ethylene glycol 1,2-Ethanediol.
Propylene glycol 1,2-Propanediol. Benzyl alcohol. Cinnamic alcohol. Cinnamic alcohol , or cinnamyl alcohol, is found in cinnamon leaves hence the name , usually in the form of an ester; it is also found in Tolu balsam, the resin of the Myroxylon toluifera tree. In case of alcohols, just as it happens in case of many other biological molecules, the basic solubility rule that like dissolves like is a bit more complexed.
Each alcohol consists of a carbon chain always nonpolar and a OH group which is polar. For ethanol for example the chemical formula looks lie this: C 2 H 5 OH. Ethanol has a 2 carbon chain and a OH group. We have tipped the scales to the hydrophilic side, and we find that glucose is quite soluble in water. We saw that ethanol was very water-soluble if it were not, drinking beer or vodka would be rather inconvenient! How about dimethyl ether, which is a constitutional isomer of ethanol but with an ether rather than an alcohol functional group?
We find that diethyl ether is much less soluble in water. Is it capable of forming hydrogen bonds with water? Yes, in fact, it is —the ether oxygen can act as a hydrogen-bond acceptor. The difference between the ether group and the alcohol group, however, is that the alcohol group is both a hydrogen bond donor and acceptor. The result is that the alcohol is able to form more energetically favorable interactions with the solvent compared to the ether, and the alcohol is therefore more soluble.
Here is another easy experiment that can be done with proper supervision in an organic laboratory. Try dissolving benzoic acid crystals in room temperature water — you'll find that it is not soluble. As we will learn when we study acid-base chemistry in a later chapter, carboxylic acids such as benzoic acid are relatively weak acids, and thus exist mostly in the acidic protonated form when added to pure water.
Acetic acid, however, is quite soluble. This is easy to explain using the small alcohol vs large alcohol argument: the hydrogen-bonding, hydrophilic effect of the carboxylic acid group is powerful enough to overcome the hydrophobic effect of a single methyl group on acetic acid, but not the larger hydrophobic effect of the 6-carbon benzene group on benzoic acid.
Now, try slowly adding some aqueous sodium hydroxide to the flask containing undissolved benzoic acid. As the solvent becomes more and more basic, the benzoic acid begins to dissolve, until it is completely in solution. What is happening here is that the benzoic acid is being converted to its conjugate base, benzoate.
The neutral carboxylic acid group was not hydrophilic enough to make up for the hydrophobic benzene ring, but the carboxylate group, with its full negative charge , is much more hydrophilic. Now, the balance is tipped in favor of water solubility, as the powerfully hydrophilic anion part of the molecule drags the hydrophobic part, kicking and screaming, if a benzene ring can kick and scream into solution.
If you want to precipitate the benzoic acid back out of solution, you can simply add enough hydrochloric acid to neutralize the solution and reprotonate the carboxylate. If you are taking a lab component of your organic chemistry course, you will probably do at least one experiment in which you will use this phenomenon to separate an organic acid like benzoic acid from a hydrocarbon compound like biphenyl. Similar arguments can be made to rationalize the solubility of different organic compounds in nonpolar or slightly polar solvents.
In general, the greater the content of charged and polar groups in a molecule, the less soluble it tends to be in solvents such as hexane. The ionic and very hydrophilic sodium chloride, for example, is not at all soluble in hexane solvent, while the hydrophobic biphenyl is very soluble in hexane. Exercise 2. Decide on a classification for each of the vitamins shown below. Hint — in this context, aniline is basic, phenol is not!
Because water is the biological solvent, most biological organic molecules, in order to maintain water-solubility, contain one or more charged functional groups.
These are most often phosphate, ammonium or carboxylate, all of which are charged when dissolved in an aqueous solution buffered to pH 7. Some biomolecules, in contrast, contain distinctly hydrophobic components. In a biological membrane structure, lipid molecules are arranged in a spherical bilayer: hydrophobic tails point inward and bind together by van der Waals forces, while the hydrophilic head groups form the inner and outer surfaces in contact with water.
Interactive 3D Image of a lipid bilayer BioTopics.
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