Cyclic compounds nomenclature

Pedersen prepared a series of macrocyclic polyethers, cyclic compounds containing four or more oxygens in a ring of 12 or more atoms. He called these compounds crown ethers, because their molecular- models resemble crowns. Systematic nomenclature of crown ethers is somewhat cumbersome, and so Pedersen devised a shorthand description whereby the word crown is preceded by the total number of atoms in the ring and is followed by the number of oxygen atoms. 

Ketones. Acyclic ketones are named (1) by adding the suffix -one to the name of the hydrocarbon forming the principal chain or (2) by citing the names of the radicals R1 and R2 followed by the word ketone. In addition to the preceding nomenclature, acyclic monoacyl derivatives of cyclic compounds may be named (3) by prefixing the name of the acyl group to the name of the cyclic compound. For example,... 

The 191 problems in this book cover most of the area of stereochemistry, including nomenclature, stereogenic elements (centers, axes, planes) and their descriptors, symmetry, inorganic stereochemistry, determination of enantiomer excess, conformation of acyclic and cyclic compounds, and more. The answers, in addition to providing solutions to the problems, frequently include additional explanations of the underlying principles. The problems are ordered more or less in order of increasing difficulty. (I had a hard time with some of the problems toward the end myself )... 

Cyclic Compounds. The Patterson-Capell Ring Index is the greatest single contribution to chemical nomenclature of recent years. Yet it has not been adopted in toto in Britain because some older methods are retained which are in general based on those of Richter. One principle, for instance, which is not favored is exemplified by the varied numbering of, say, the indene skeleton for which there... 

I cyclo- is the prefix used in j chemical nomenclature to des- ignate a cyclic compound. 

An important note that concerns substituents on cyclic compounds must be reiterated The E/Z nomenclature just discussed is never used with cyclic compounds, only with alkenes. 

For linear diterpenes or the linear segments of cyclic compounds with ambiguous double bond stereochemistries, the steric relationship about the double bond is indicated by a Z or E suffix (e.g., 13(14)E, 2(3)Z). The Z or E assignment results from the comparison of the sequence-rule-preference of the four atoms attached to the doubly bonded carbons (as specified in Rule E-2.2. of the lUPAC Rules for Nomenclature of Organic Chemistry). Several examples of Z and E assignment are discussed below in order to familiarize the reader with this method. 

Differently from what commonly reported for the nomenclature of cyclic compounds bearing doubly substituted stereocenters [Cross, L. C. Klyne, W. PureAppl. Chem. 1976, 45, 11-30], for our convenience the cis/trans notation wiU he hereafter employed to indicate the relative configuration of the methoxy groups in 41a and its achiral congeners. 

Another very specific subtractive naming mode has been developed for cyclic compounds containing (if only formal) contiguous double bonds -cyclic cumulenes - whose treatment with conventional nomenclatural means would often lead to rather cumbersome combinations of ene , dehydro , and indicated H notations. 

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... 

Cyclic ethers are named either as heterocyclic compounds or by specialist rules of heterocyclic nomenclature. Radicofunctional names are formed by citing the names of the radicals R and R followed by the word ether. Thus methoxyethane becomes ethyl methyl ether and ethoxyethane becomes diethyl ether. 

There is some evidence that Cs + can be formed by cyclic voltammetry of Cs+[OTeF5] in pure MeCN at the extremely high oxidizing potential of 3 V, and that Cs + might be stabilized by 18-crown-6 and cryptand (see pp. 96 and 97 for nomenclature). However, the isolation of pure compounds containing Cs + has so far not been reported. 

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... 

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