Cation names cations

Polyatomic Cations. Polyatomic cations derived by addition of more protons than required to give a neutral unit to polyatomic anions are named by adding the ending -onium to the root of the name of the anion element for example, PH4, phosphonium ion HjU, iodonium ion H3O+, oxonium ion CH3OHJ, methyl oxonium ion. 

Substituted ammonium ions derived from nitrogen bases with names ending in -amine receive names formed by changing -amine into -ammonium. When known by a name not ending in -amine, the cation name is formed by adding the ending -ium to the name of the base (eliding the final vowel) e.g., anilinium, hydrazinium, imidazolium, acetonium, dioxanium. 

The methods for naming cations and anions may be combined to name zwitterions the cationic center is cited before the anionic center, both in the replacement prefixes and in the suffixes, e.g. (204). One should be aware, however, that Chemical Abstracts names zwitterions by an extraordinary circumlocution, in which water is hypothetically added and then hypothetically taken away, to give names consisting of four separate words ending in inner salt, e.g. (205). 

TIricooRlinate caibocations are fiequendy called carbonium ions. The terms methyl cation, butyl cation, etc., are used to describe the c >rTesixiiulir.ji tricoordinate cations. Chemical Abstracts uses as specific names methylium, ethyUum, propylium. We will use carbocation as a generic term for trivalent carbon cations. 

As mentioned at the end of Section 8.3, the MO investigation by Apeloig and Arad (1985) of the influence of trimethylsilyl substituents on the phenyl cation led to the discovery of a further reagent, in addition to arenediazonium ions, that is able to form aryl cations, namely 2,6-bis-(trimethylsilyl)phenyltriflate. This was a significant success in the field of predictions on aryl cations by theoretical work. 

An ionic compound is named with the cation name first, followed by the name of the anion the word ion is omitted in each case. The oxidation number of the cation is given if more than one charge is possible. However, if the cation comes from an element that exists in only one charge state (as listed in Fig. C.6), then the oxidation number is omitted. Typical names include potassium chloride (KC1), a compound containing K+ and Cl" ions and ammonium nitrate (NH4NOs), which contains NH4+ and NO3" ions. The cobalt chloride that contains Co2+ ions (CoCl,) is called cobalt(II) chloride C0CI3 contains Co3+ ions and is called cobalt(III) chloride. 

The name of a coordination compound (as distinct from a complex cation or anion) is built in the same way as that of a simple compound, with the cation named before the anion ... 

Calculation of the second-order rate constant of carbonylation, kg, and the equilibrium constant, K = [t-C4H9CO+]/[t-C4H ][CO] = A c/fcD> requires knowledge of the concentration of CO. The constant a in Henry s law Pco = [CO] was determined to be 5-3 litre mole atm in HF—SbFs (equimolar) and 53 litre mole atm in FHSOs—SbFs (equimolar) at 20°C. From the ratio [t-C4HBCO+]/[t-C4HJ"] at a known CO pressure, values for k and K were obtained. The data are listed in Table 1, which includes the values for the rate and equilibrium constants of two other tertiary alkyl cations, namely the t-pentyl and the t-adamantyl ions (Hogeveen et al., 1970). 

Ionic compounds are named using the same guidelines used for naming binary molecules, except that the cation name aiways precedes the anion name. Thus, NH4 NO3 is ammonium nitrate, Na2 CO3 is sodium carbonate, and Ca3 (P04)2 is caicium phosphate. The subscripts are not specified in these names because the fixed ionic charges determine the cation-anion ratios unambiguously. Example 3-6 reinforces these guidelines by showing how to construct chemicai formulas from chemical names. 

Cr03 As a transition metal, chromium forms more than one stable cation. Name the metal first, using a Roman numeral to designate chromium s charge. Each of the three oxide anions has a -2 charge. To maintain net charge neutrality, Cr must be +6, so the name of the compound is chromium(VI) oxide. 

Compounds which have low IP and sufficient charge localization in the radical cation, namely 7-methylbenz[a]anthracene, BP,... 

Chronologically, Sato and coworkers have been the first to obtain and to characterized unambiguously a fractional oxidation state compound containing the Ni (dmit)2 unit and an SCO cation, namely [Fe(qsal)2][Ni(dmit)2]3.CH3CN.H20 [106]. This complex has been obtained after electrocrystallization from an acetonitrile solution of [Fe(qsal)2][Ni(dmit)2].2CH3CN. 

Monatomic Cations. Monatomic cations are named as the corresponding element for example, Fe2+, iron(II) ion Fe3+, iron(III) ion. 

A The name of each of these ionic compounds is the name of the cation followed by that of the anion. Each anion name is a modified (with the ending ide ) version of the name of the element. Each cation name is the name of the metal, with the oxidation state appended in Roman numerals in parentheses if there is more than one type of cation for that metal. 

Ammonium salts contain a nitrogen atom with four bonds that has a positive charge. Four-bonded nitrogen atoms derived from amines are ammonium ions (if they re derived from aniline, they re anilinium ions). If the four bonds are all to carbon atoms, the nitrogen atom is quaternary. Salts contain a cation (named first) and an anion (named last). Typical anions include Cl (chloride), Bi" (bromide), HSO (hydrogen sulfate or bisulfate), and NOj-(nitrate). Figure 13-5 shows two examples of ammonium ions. 

The symbols (formulae) are listed in alphabetical order according to the principles outlined above. Because the terminations -ous and -ic for metal cation names are no longer recommended, these have been excluded, but we have attempted to include all those traditional names that are still allowed. We have not attempted to present names for species of very rare or unlikely occurrence, so there are gaps in the columns. 

Classification of Solvents in Terms of Specific Solute-Solvent Interactions Parker divided solvents into two groups according to their specific interactions with anions and cations, namely dipolar aprotic solvents and protic solvents (Parker, 1969). The distinction lies principally in the dipolarity of the solvent molecules and their ability to form hydrogen bonds. It appears appropriate to add to these two groups a third one, namely, the apolar aprotic solvents. 

These compounds are all ordinciry ionic compounds, so you simply need to pair the cation name with the anion name and change the anion name s ending to -ide. 

Oxidation of TTF and its derivatives induces the transformation from neutral species into cationic ones, namely, cation radicals (TTF +) and dications (TTF2+). Moreover, TTF, TTF +, and TTF2+ exhibit different absorption spectra. Taking these advantages of TTF new TTF-based redox fluorescence switches and chiral switches have been recently reported. 

Binding interactions available to these ions are essentially electrostatic in nature, namely, cation-anion attractions responsible for cation-pairing to counter-anions, and ion-dipole interactions that provide the basis for the well-known complexation with crown ethers. 

We may perform the same analysis for the allyl radical and the allyl anion, respectively, by adding the energy of 4>2 to the cation with each successive addition of an electron, i.e., H (allyl radical) = 2(a + V2/3) + a and Hn allyl anion) = 2(a + s/2f) + 2a. In the hypothetical fully 7T-localized non-interacting system, each new electron would go into the non-interacting p orbital, also contributing each time a factor of a to the energy (by definition of o ). Thus, the Hiickel resonance energies of the allyl radical and the allyl anion are the same as for the allyl cation, namely, 0.83/1. 

Electropositive condiments. The name of a monoatomic electropositive constituent is simply the unmodified element name. A polyatomic constituent assumes the usual cation name, but certain well established radical names (particularly for oxygen-containing species such as nitrosyl and phosphoryl) are still allowed for specific cases... 

Coordination cations. The names of complex cations are derived most simply by using the coordination cation names (see Section I—10). This is preferred whenever umbigu-ity might result. 

Names of monoaromic cations. Monoaromic cations are named by adding in parentheses after the rume of the element [either the appropriate charge number followed by the plus sign or the oxidation number (Roman numeral)] followed by the words cation or ion ... 

Because of the similar energy of the two possible resonances that can ensure hydration of the pteridine cation (namely, 4-aminopyridinium stabilization of 7,8-hydration and amidinium stabilization of 3,4-hydration3 ), a study of the effects of substituents on this delicately balanced system was undertaken. An initial survey showed that the majority of pteridine cations were subject neither to dihydration nor to shifting hydration. Only four examples were found in which 5,6,7,8-dihydration was preceded by 3,4-hydration, namely 2-methyl-, 6-methyl-, 7-methyl-, and 2-amino-4-methylpteridine, whereas the related cations of 6,7-dimethyl-, 2-amino-, 2-amino-6-methyl-, and 2-amino-7-methylpteridine remained stably hydrated in the 3,4-position.8,40 Further examples, including a reversed direction of shift, came to light from a... 

IUPAC Rules B-6 and B-10 give examples of heterocyclic cations named by replacement principles. The normal replacement prefixes... 

With this limitation in mind, one should consider the possibility of applying -ium and -ylium suffixes to ordinary replacement names (instead of using -onia- prefixes) this sort of treatment could be very useful in certain cases (see, for example, Section iii), and may prove to be the method of choice for naming cations if the use of replacement nomenclature becomes more widely accepted. By this method, 100 could be named 4aA5-4a-azanaphthalen-4a-ylium 99, 8ai/-4a-azanaphthalen-4a-ium and 103, azabenzen-1 (4f/)-ylium or azacyclo-hexa-2,5-dien-1 -ylium. 

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