Functional groups nomenclature

Hydrocarbon nomenclature Functional groups Polymers Biochemistry... 

While developing the connections between structure reaction and mechanism we will also extend the fundamentals of lUPAC nomenclature to functional group families beginning with alcohols and alkyl halides... 

Although substitutive names of the type just described are preferred the lUPAC rules also permit ketones to be named by functional class nomenclature The groups attached to the carbonyl group are named as separate words followed by the word ketone The groups are listed alphabetically... 

Frosts circle (Section 11 19) A mnemonic that gives the Huckel TT MOs for cyclic conjugated molecules and 10ns Functional class nomenclature (Section 4 2) Type of lUPAC nomenclature in which compounds are named according to functional group families The last word in the name... 

Substitutive Nomenclature. The first step is to determine the kind of characteristic (functional) group for use as the principal group of the parent compound. A characteristic group is a recognized combination of atoms that confers characteristic chemical properties on the molecule in which it occurs. Carbon-to-carbon unsaturation and heteroatoms in rings are considered nonfunctional for nomenclature purposes. 

Systematic names formed by applying the principles of substitutive nomenclature are single words except for compounds named as acids. First one selects the parent compound, and thus the suffix, from the characteristic group listed earliest in Table 1.7. All remaining functional groups are handled as prefixes that precede, in alphabetical order, the parent name. Two examples may be helpful ... 

The common method of naming aldehydes corresponds very closely to that of the related acids (see Carboxylic acids), in that the term aldehyde is added to the base name of the acid. For example, formaldehyde (qv) comes from formic acid, acetaldehyde (qv) from acetic acid, and butyraldehyde (qv) from butyric acid. If the compound contains more than two aldehyde groups, or is cycHc, the name is formed using carbaldehyde to indicate the functionaUty. The lUPAC system of aldehyde nomenclature drops the final e from the name of the parent acycHc hydrocarbon and adds al If two aldehyde functional groups are present, the suffix -dialis used. The prefix formjlis used with polyfunctional compounds. Examples of nomenclature types are shown in Table 1. 

Sulfides are sulfur analogs of ethers they contain the C—S—C functional group. They are named as alkylthio derivatives of alkanes in substitutive lUPAC nomenclature. The functional class lUPAC nmnes of sulfides are derived in the same manner as those of ethers, but the concluding word is sulfide. 

In this presentation, the following nomenclature will be used for commonly occurring functional groups ... 

A chemical name typically has four parts in the IUPAC system of nomenclature prefix, locant, parent, and suffix. The prefix specifies the location and identity of various substituent groups in the molecule, the locant gives the location of the primary functional group, the parent selects a main part of the molecule and tells how many carbon atoms are in that part, and the suffix identifies the primary functional group. 

As we cover new functional groups in later chapters, the applicable IUPAC rules of nomenclature will be given. In addition, Appendix A at the back of this book gives an overall view of organic nomenclature and shows how compounds that contain more than one functional group are named. For the present, let s see how to name branched-chain alkanes and learn some general naming rules that are applicable to all compounds. 

Alkanes are a class of saturated hydrocarbons with the general formula C H2n. -2- They contain no functional groups, are relatively inert, and can be either straight-chain (normal) or branched. Alkanes are named by a series of IUPAC rules of nomenclature. Compounds that have the same chemical formula but different structures are called isomers. More specifically, compounds such as butane and isobutane, which differ in their connections between atoms, are called constitutional isomers. 

As noted in the text, chemists overwhelmingly use the nomenclature system devised and maintained by the International Union of Pure and Applied Chemistry, or IUPAC. Rules for naming monofunctional compounds were given throughout the text as each new functional group was introduced, and a list of where these rules can be found is given in Table A.l. 

Although a polyfunctional organic molecule might contain several different functional groups, we must choose just one suffix for nomenclature purposes. It s not correct to use two suffixes. Thus, keto ester 1 must be named either as a ketone with an -one suffix or as an ester with an -oate suffix but can t be named as an -onoate. Similarly, amino alcohol 2 must be named either as an alcohol (-0/) or as an amine (-amine) but can t be named as an -olamine or -anritiol. 

The parent that includes the functional group most preferred by general principles of organic nomenclature [13,14], If there is a choice, it is made on the basis of the greatest number of occurrences of the most preferred functional group. Thus aldaric acid > uronic acid/ketoaldonic acid/aldonic acid > dialdose > ketoal-dose/aldose > diketose > ketose. 

Introduction to organic chemistry hydrocarbons and functional groups (structure, nomenclature, chemical properties). Physical and chemical properties of simple organic compounds should also be included as exemplary material for the study of other areas such as bonding, equilibria involving weak acids, kinetics, colligative properties, and stoichiometric determinations of empirical and molecular formulas. 

Nomenclature based on a parent term with an appended suffix accounts for most natural product names. However, as related compounds are identified, or even when a suffix has to denote multiple functional groups, a variety of modifying terms can be employed. For example, the common prefix nor- denotes the removal of a skeletal atom from the parent structure the loss of two or more skeletal atoms is indicated by combining an appropriate numerical prefix with nor- , e.g., dinor- , trinor- (Giles 1999). Table 1.2 lists additional examples of commonly encountered modifying terms. 

The cyclic forms adopted by the hexoses and pentoses can be depicted as symmetrical ring structures called Haworth projection formulae, which give a better representation of the spatial arrangement of the functional groups with respect to one another. The nomenclature is based on the simplest organic compounds exhibiting a similar five- or six-membered ring... 

However, most coupling chemistries do not go to completion so that the substrate will contain a mixture of functional groups capped with attached probe (SR) while others remain free (S ). These residual reachve functional groups must be capped or blocked in some manner to reduce nonspecific binding to the microarray. Residual surface amines may be capped by reaction with succinic anhydride. This renders the support neutral (SR). Using this abbreviated nomenclature, we can describe common surface modifications for microarray substrates. 

Alternative names are shown in some cases this should emphasize that there is often no unique correct name. Sometimes, it can be advantageous to bend the rules a little so as to provide a neat name rather than a fully systematic one. Typically, this might mean adopting a lower priority functional group as the suffix name. It is important to view nomenclature as a means of conveying an acceptable unambiguous stmc-ture rather than a rather meaningless scholastic exercise. Other examples will occur in subsequent chapters, and specialized aspects, e.g. heterocyclic nomenclature, will be treated in more detail at the appropriate time (see Chapter 11). Stereochemical descriptors are omitted here, but will be discussed under stereochemistry (see Sections 3.4.2 and 3.4.3). 

In Chapter 3 we go into some depth about alcohols and ethers. Like Organic 1, when we encounter a new functional group we examine the structure, nomenclature, properties, synthesis, and reactions. In some courses and textbooks, alcohols are covered in the first semester, but for those readers who haven t gotten to them yet, we include them in this book. If you re already comfortable with that material, please feel free to skip that chapter and go on to another. 

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