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The Phenyl Group. As mentioned previously, the phenyl group (Ph-R, C 6 H 5-R) can be formed by removing a hydrogen from benzene and attaching a substituent to where the hydrogen was healthgrabber.us this phenomenon, we can name compounds formed this way by applying this rule: (phenyl + substituent).For example, a chlorine attached in this manner would be named phenyl chloride, and a . If there are fewer than six carbon atoms in the chain, the compound is named as a substituted benzene. The phenyl group can be abbreviated in chemical structures as -Ph or sometimes as the Greek letter phi, - φ. Benzene is a cyclic compound containing six carbon atoms and six hydrogen atoms. The molecular formula for benzene, C 6 H 6, was determined soon after it was isolated by Michael Faraday in .
You should already know the names and structures of several of the hydrocarbons shown in Figure A compound containing a benzene ring which has one or more alkyl substituents is called an arene. You should memorize the structures and formulas shown in Figure You will meet these compounds frequently throughout the remainder of this course. Unlike aliphatic organics, nomenclature of benzene-derived compounds can be confusing because a single aromatic compound can have multiple possible names such as common and systematic names be associated with its structure.
In these sections, we will analyze some of the ways these compounds can be named. Some common substituents, like NO 2Br, and Cl, can be named this way when it is attached to how to name phenyl groups phenyl group. Long chain carbons attached can also be named this way. The general format for this kind of naming is:. Since there is only one substituent on the benzene ring, we do not have to indicate its position on the benzene ring as it can freely rotate around and you would end up getting the same compound.
Figure 8. Example of simple benzene naming with chlorine and NO 2 as substituents. Figure 9. More complicated simple benzene naming examples - Note that standard nomenclature priority rules are applied here, causing the numbering of carbons to switch. See Nomenclature of Organic Compounds for a review on naming and priority rules. Instead of using numbers to indicate substituents on a benzene ring, ortho- o-meta- m-or para p- can be used in place of positional markers when there are two substituents on the benzene ring disubstituted benzenes.
They are defined as the following:. Using the same example above in figure 9a 1,3-dichlorobenzene how to name phenyl groups, we can use the ortho- meta- para- nomenclature to transform the chemical name into m-dichlorobenzene, as shown in the figure below. Figure Transformation of 1,3-dichlorobenzene into m-dichlorobenzene. Here are some other examples of ortho- meta- para- nomenclature used in context:.
However, the substituents used in ortho- meta- para- nomenclature do not have to be the same. For example, we can use chlorine and a nitro group as substituents in the benzene ring.
In conclusion, these can be pieced together into a summary diagram, as shown below:. In addition to simple benzene naming and OMP nomenclature, benzene derived compounds are also sometimes used as bases.
The concept of a base is similar to the nomenclature of aliphatic and cyclic compounds, where the parent for the what was the first black college in america compound is used as a base a name for its chemical name.
For example, the following compounds have the base names hexane and cyclohexanerespectively. See Nomenclature of Organic Compounds for a review on naming organic what to do for sleep apnea. Benzene, similar to these compounds shown above, also has base names from its derived compounds. Phenol C 6 H 5 OHas introduced previously in this article, for example, serves as a base when other substituents are attached to it.
This is best illustrated in the diagram below. An example showing phenol as a base in its chemical name. Note how benzene no longer serves as a base when an OH group is added to the benzene ring. Alternatively, we can use the numbering system to indicate this compound.
When the numbering system is used, the carbon where the substituent is attached on the base will be given the first priority and named as carbon 1 C 1. The normal priority rules then apply in the nomenclature process give the rest of the substituents the lowest numbering as you could. The naming process for 2-chlorophenol o-chlorophenol.
Below is a list of commonly seen benzene-derived compounds. Some of these mono-substituted compounds labeled in red and greensuch as phenol or toluene, can be used in place of benzene for the chemical's base name. Common benzene derived compounds with various substituents. According to the indexing preferences of the Chemical Abstractswhat to look for at home inspection, benzaldehyde, and benzoic acid labeled in red in Figure 16 are some of the common names that are retained in the IUPAC systematic nomenclature.
Other names such as toluene, styrene, naphthalene, or phenanthrene can also be seen in the IUPAC system in the same way. While the use of other common names are usually acceptable in IUPAC, their use are discouraged in the nomenclature of compounds.
Nomenclature for compounds which has such discouraged names will be named by the simple benzene naming system. An example of this would include toluene what is a brazillan wax like TNT.
Note that toluene by itself is retained by the IUPAC nomenclature, but its derivatives, which contains additional substituents on the benzene ring, might be excluded from the convention. For this reason, the common chemical name 2,4,6-trinitrotoluene, or TNT, as shown in figure 17, would not be advisable under the IUPAC systematic nomenclature.
Note that the methyl group is individually named due to the exclusion of toluene from the IUPAC nomenclature. Only substituents phenol, benzoic acid, and benzaldehyde share this commonality.
For this reason, the OMP system will yield common names that can be converted to systematic names by using the same method as above. As mentioned previously, the phenyl group Ph-R, C 6 H 5 -R can be formed by removing a hydrogen from benzene and attaching a substituent to where the hydrogen was removed.
For example, a chlorine attached in this manner would be named phenyl chlorideand a bromine attached in this manner would be named phenyl bromide. See below diagram. Naming of Phenyl Chloride and Phenyl Bromide. While compounds like these are usually named by simple benzene type naming chlorobenzene and bromobenzenethe phenyl group naming is usually applied to how to make plaster masks rings where a substituent with six or more carbons is attached, such as in the diagram below.
Diagram of 2-phenyloctane. Although the diagram above might be a little daunting to understand at first, it is not as difficult as it seems after careful analysis of the structure is made. By looking for how to name phenyl groups longest chain in the compound, it should be clear that the longest chain is eight 8 carbons long octane, as shown in green and that a benzene ring is attached to the second position of this longest chain labeled in red.
As this rule suggests that the benzene ring will act as a function group a substituent whenever a substituent of more than six 6 carbons is attached to it, the name "benzene" is changed to phenyl and is used the same way as any other substituents, such as methylethyl, or bromo. Putting it all together, the name can be derived as: 2-phenyloctane phenyl is attached at the second position of the longest carbon chain, octane.
The benzyl group abbv. Bnsimilar to the phenyl group, is formed by manipulating the benzene ring. In the case of the benzyl group, it is formed by taking the phenyl group and adding a CH 2 group to where the hydrogen was removed. Nomenclature of benzyl group based compounds are very similar to the phenyl group compounds. For example, a chlorine attached to a benzyl group would simply be called benzyl chloride, whereas an OH group attached to a benzyl group would simply be called benzyl alcohol.
Benzyl Group Nomenclature. Additionally, other substituents can attach on the benzene ring in the presence of the benzyl group. An example of this can be how to name phenyl groups in the figure below:. Nomenclature of 2,4-difluorobenzyl chloride. Similar to the base name nomenclatures system, the carbon in which th base substitutent is attached on the benzene ring is given the first priority and the rest of the substituents are given the lowest number order possible.
Similar to the base name nomenclature system, the carbon in which the base substituent is attached on the benzene ring is given the first priority and the rest of the substituents are given the lowest number order possible. Under this consideration, the above compound can be named: 2,4-difluorobenzyl chloride. Summary Flowchart Figure Summary of nomenclature rules used in commonly benzene derived compounds.
As benzene derived compounds can be extremely complex, only compounds covered in this article and other commonly named compounds can be named using this flowchart. To demonstrate how this flowchart can be used to name TNT in its common and systematic IUPAC name, a replica of the flowchart with the appropriate flow paths are shown below:. Menthol, a how to burn trash for energy analgesic used in many ointments for the relief of pain, releases a peppermint aroma upon exposure to the air.
Based on this conclusion, can you imply that a benzene ring is present in its chemical structure? Why or why not? No, a substance that is fragrant does not imply a benzene ring is in its structure. See camphor example figure 1. No reaction, benzene requires a special catalyst to how to name phenyl groups hydrogenated due to its unusual stability given by its three conjugated pi bonds.
False, the correct abbreviation for the benzyl group is Bn, not Bz. The correct abbreviation for Benzyl chloride is Bn-Cl. TNT, for example, has the common name 2,4,6-trinitrotoluene and its systematic name is 2-methyl-1,3,5-trinitrobenzene. A scientist has conducted an experiment on an unknown compound. He was able to determine that the unknown compound contains a cyclic ring in its structure as well as an alcohol -OH group attached to the ring.
What is the unknown compound? The correct answer is f. We cannot determine what structure this is since the question does not tell us what kind of cyclic ring the -OH group is attached on.
Just as cyclohexane can be cyclic, benzene and cycloheptane can also be cyclic. Which of the following statements is false for the compound, phenol? Name the following compounds. Steven Farmer Sonoma State University. Objectives After completing this section, you should be able to draw the structure of each of the common aromatic compounds in Figure 16 Common benzene derived compounds with various substituentsgiven their IUPAC-accepted trivial names.
Key Terms Make certain that you can define, and use in context, the key terms below. Study Notes You should already know the names and structures of several of the hydrocarbons shown in Figure A phenyl group consists of a benzene ring with one of its hydrogens removed.
Ortho- Meta- Para- OMP Nomenclature for Disubstituted Benzenes Instead of using numbers to indicate substituents on a benzene ring, ortho- o-meta- m-or para p- can be used in place of positional markers when there are two substituents on the benzene ring disubstituted benzenes.
The Phenyl Group. As mentioned previously, the phenyl group (Ph-R, C 6 H 5-R) can be formed by removing a hydrogen from benzene and attaching a substituent to where the hydrogen was removed. To this phenomenon, we can name compounds formed this way by applying this rule: (phenyl + substituent). Cases where the name is based on phenyl. Remember that the phenyl group is a benzene ring minus a hydrogen atom - C 6 H 5. If you draw a benzene ring with one group attached, you have drawn a phenyl group. phenylamine. Phenylamine is a primary amine and contains the -NH 2 group attached to a benzene ring. The old name for phenylamine is aniline, and you could also reasonably call it . Phenyl group is also referred to as aryl phenols, are compounds composed of a phenolic group connected directly to another aromatic ring. Any functional group containing an aromatic group, an aryl group is represented by Ar. Phenyl group is formed when a .
In organic chemistry , the phenyl group , or phenyl ring , is a cyclic group of atoms with the formula C 6 H 5. Phenyl groups are closely related to benzene and can be viewed as a benzene ring, minus a hydrogen, which may be replaced by some other element or compound to serve as a functional group. Phenyl groups have six carbon atoms bonded together in a hexagonal planar ring, five of which are bonded to individual hydrogen atoms, with the remaining carbon bonded to a substituent.
Phenyl groups are commonplace in organic chemistry. Benzene is sometimes denoted as PhH. Phenyl groups are generally attached to other atoms or groups.
For example, triphenylmethane Ph 3 CH has three phenyl groups attached to the same carbon center. Many or even most phenyl compounds are not described with the term "phenyl".
For example, the chloro derivative C 6 H 5 Cl is normally called chlorobenzene , although it could be called phenyl chloride. Although Ph and phenyl uniquely denote C 6 H 5 , substituted derivatives also are described using the phenyl terminology. Monosubstituted phenyl groups that is, disubstituted benzenes are associated with electrophilic aromatic substitution reactions and the products follow the arene substitution pattern. So, a given substituted phenyl compound has three isomers, ortho 1,2-disubstitution , meta 1,3-disubstitution and para 1,4-disubstitution.
A disubstituted phenyl compound trisubstituted benzene may be, for example, 1,3,5-trisubstituted or 1,2,3-trisubstituted. Higher degrees of substitution, of which the pentafluorophenyl group is an example, exist and are named according to IUPAC nomenclature. Phenyl compounds are derived from benzene C 6 H 6 , at least conceptually and often in terms of their production. In terms of its electronic properties, the phenyl group is related to a vinyl group.
Phenyl groups tend to resist oxidation and reduction. Phenyl groups like all aromatic compounds have enhanced stability in comparison to equivalent bonding in aliphatic non-aromatic groups. This increased stability is due to the unique properties of aromatic molecular orbitals.
The bond lengths between carbon atoms in a phenyl group are approximately 1. In 1 H- NMR spectroscopy, protons of a phenyl group typically have chemical shifts around 7. These chemical shifts are influenced by aromatic ring current and may change depending on substituents. Phenyl groups are usually introduced using reagents that behave as sources of the phenyl anion or the phenyl cation. Electrophiles attack benzene to give phenyl derivatives:.
These reactions are called electrophilic aromatic substitutions. Atorvastatin Lipitor , a blockbuster drug featuring two phenyl and one p -fluorophenyl groups. It is used to lower cholesterol in people with hypercholesterolaemia. Fexofenadine Allegra, Telfast , another blockbuster drug, which features a diphenylmethyl group as well as a p - phenylene C 6 H 4 group.
It is an antihistamine used to treat allergies. Biphenyl , consisting of two phenyl groups. The two rings tend not to be coplanar. Chlorobenzene or phenyl chloride , a solvent. Phenyl groups are found in many organic compounds, both natural and synthetic see figure. Most common among natural products is the amino acid phenylalanine , which contains a phenyl group.
A major product of the petrochemical industry is " BTX " consisting of benzene, toluene, and xylene - all of which are building blocks for phenyl compounds. The polymer polystyrene is derived from a phenyl-containing monomer and owes its properties to the rigidity and hydrophobicity of the phenyl groups. Many drugs as well as many pollutants contain phenyl rings.
One of the simplest phenyl-containing compounds is phenol , C 6 H 5 OH. However, a significant contribution is the greater electronegativity of the sp 2 alpha carbon in phenol compared to the sp 3 alpha carbon in aliphatic alcohols.
From Wikipedia, the free encyclopedia. Redirected from Phenyl. Phenylalanine , a common amino acid. Advanced organic chemistry: reactions, mechanisms, and structure 4th ed. New York: Wiley. ISBN Benzene and Other Aromatic Compounds".
Virtual Textbook of Organic Chemistry. Michigan State University. English by Lexico Dictionaries. Retrieved 24 July Organic Chemistry, Enhanced Edition.
Cengage Learning. Chemical Reviews. ISSN The Journal of Organic Chemistry. PMID Functional groups. Phosphonate Phosphonous. Selenol Selenonic acid Seleninic acid Selenenic acid Selone. Tellurol Telluroketone. See also chemical classification chemical nomenclature inorganic organic. Categories : Aryl groups Phenyl compounds. Hidden categories: Articles with short description Short description is different from Wikidata Articles containing French-language text Articles containing Greek-language text Commons category link from Wikidata Wikipedia articles with GND identifiers Wikipedia articles with MA identifiers.
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