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Grouping words

We can also consider the phonological hierarchy, which is a different, parallel hierarchy which focuses on the sound patterns in a sentence. In this, we have the additional units of syllables, which are a structural sound unit used to group phonemes together and phonological phrases, another structural sound unit that groups words together within the sentence. Representations using these units can also be expressed in a hierarchy of sentences, prosodic phrases, words, syllables and phonemes. [Pg.16]

Phrasing is used to group words together in the utterance, and is influenced by top down factors such as syntax, and bottom up factors which place phrase breaks at roughly equal intervals. [Pg.145]

Most work agrees that the prosodic phrase as described in Section 6.2 is the basic domain of intonational tune patterns. Hence the phrase not only groups words together, it also serves as the start and end of each section of tune. In many models, we have a nuclear accent, which occurs once per phrase. [Pg.232]

In Sections V.A.1-V.A.3, we treated one particular group of t mabices as presented in Eq. (51), where g is an antisymmebic matrix with constant elements. The general theory demands that the mabix D as presented in Eq. (52) be diagonal and that as such it contains (-1-1) and (—1) values in its diagonal. In the three examples that were worked out, we found that for this particular class of T mabices the coiiesponding D mabix contains either (-1-1) or (—1) terms but never a mixture of the two types. In other words, the D mab ix can be represented in the following way ... [Pg.657]

Organic compounds M—R and hydrides M—H of main group metals such as Mg, Zn, B, Al, Sn, SI, and Hg react with A—Pd—X complexes formed by oxidative addition, and an organic group or hydride is transferred to Pd by exchange reaction of X with R or H. In other words, the alkylation of Pd takes place (eq. 9). A driving force of the reaction, which is called transmetallation, is ascribed to the difference in the electronegativities of two metals. A typical example is the phenylation of phenylpalladium iodide with phenyltributyltin to form diphenylpalladium (16). [Pg.8]

Allylamines are difficult to cleave with Pd catalysts. Therefore, amines are protected as carbamates, but not as allylamines. Also, allyl ethers used for the protection of alcohols cannot be cleaved smoothly, hence alcohols are protected as carbonates. In other words, amines and alcohols are protected by an allyloxycarbonyl (AOC or Alloc) group. [Pg.382]

The effect of alkyl groups in the 5-position on the reactivity of the thiazole nitrogen is analogous to that found for 3-alkylpyridines, in other words, a simple inductive effect. In passing from the unsubstituted heterocycle to the methyl derivative, the rate constant doubles a further increase in substitution produces a much less pronounced variation. [Pg.390]

Write the name of the compound The parent alkane is the last part of the name and is preceded by the names of the substituent groups and their numerical locations (locants) Hyphens separate the locants from the words... [Pg.72]

Both remaining CgHi4 isomers have two methyl groups as substituents on a four carbon chain Thus the parent chain is butane When the same substituent appears more than once use the multiplying prefixes di tri tetra and so on A separate locant is used for each substituent and the locants are separated from each other by commas and from the words by hyphens... [Pg.73]

The lUPAC rules permit alkyl halides to be named m two different ways called func twnal class nomenclature and substitutive nomenclature In functional class nomencla ture the alkyl group and the halide (fluoride chloride bromide or iodide) are desig nated as separate words The alkyl group is named on the basis of its longest continuous chain beginning at the carbon to which the halogen is attached... [Pg.144]

Functional class names of alcohols are derived by naming the alkyl group that bears the hydroxyl substituent (—OH) and then adding alcohol as a separate word The chain IS always numbered beginning at the carbon to which the hydroxyl group is attached... [Pg.145]

One way to name carbo cations in the lUPAC system IS to add the word cation to the name of the alkyl group... [Pg.156]

The substitutive names of alcohols are derived by replacing the e end mg of an alkane with ol The longest chain containing the OH group becomes the basis for the name Functional class names of alcohols begin with the name of the alkyl group and end m the word alcohol... [Pg.179]

Allyl IS derived from the botanical name for garlic Allium sativum) It was found in 1892 that the major component obtained by distilling garlic oil is H2C=CHCH2SSCH2CH=CH2 and the word a//y/was coined for the H2C=CHCH2— group on the basis of this origin... [Pg.390]

When the benzene ring is named as a substituent the word phenyl stands for CgH5— Similarly an arene named as a substituent is called an aryl group A benzyl group IS CgHjCH,—... [Pg.434]

Ethers are named m substitutive lUPAC nomenclature as alkoxy derivatives of alkanes Functional class lUPAC names of ethers are derived by listing the two alkyl groups m the general structure ROR m alphabetical order as separate words and then adding the word ether at the end When both alkyl groups are the same the prefix di precedes the name of the alkyl group... [Pg.665]

Section 16 1 Ethers are compounds that contain a C—O—C linkage In substitutive lUPAC nomenclature they are named as al/coxy derivatives of alkanes In functional class lUPAC nomenclature we name each alkyl group as a separate word (m alphabetical order) followed by the word ether... [Pg.691]

Sulfides are sulfur analogs of ethers they contain the C—S—C func tional group They are named as al/cylthw derivatives of alkanes m sub stitutive lUPAC nomenclature The functional class lUPAC names of sul tides are derived m the same manner as those of ethers but the concluding word is sulfide... [Pg.691]

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... [Pg.705]

Ketones may also be named using functional class lUPAC nomenclature by citing the two groups attached to the carbonyl m alphabetical order followed by the word ketone Thus 3 methyl 2 butanone (substitutive) becomes isopropyl methyl ketone (functional class)... [Pg.741]

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... [Pg.1284]

If the same alkyl group occurs more than once as a side chain, this is indicated by the prefixes di-, tri-, tetra-, etc. Side chains are cited in alphabetical order (before insertion of any multiplying prefix). The name of a complex radical (side chain) is considered to begin with the first letter of its complete name. Where names of complex radicals are composed of identical words, priority for citation is given to that radical which contains the lowest-numbered locant at the first cited point of difference in the radical. If two or more side chains are in equivalent positions, the one to be assigned the lowest-numbered locant is that cited first in the name. The complete expression for the side chain may be enclosed in parentheses for clarity or the carbon atoms in side chains may be indicated by primed locants. [Pg.2]

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 ... [Pg.17]

Acetals and Acylals. Acetals, which contain the group >C(OR)2, where R may be different, are named (1) as dialkoxy compounds or (2) by the name of the corresponding aldehyde or ketone followed by the name of the hydrocarbon radical(s) followed by the word acetal. For example, CH3—CH(0CH3)2 is named either (1) 1,1-dimethoxyethane or (2) acetaldehyde dimethyl acetal. [Pg.23]

For oximes, the word oxime is placed after the name of the aldehyde or ketone. If the carbonyl group is not the principal group, use the prefix hydroxyimino-. Compounds with the group Z = N—OR are named by a prefix alkyloxyimino- as oxime O-ethers or as O-substituted oximes. Compounds with the group r C=N(0)R are named by adding A-oxide after the name of the alkylideneaminc compound. For amine oxides, add the word oxide after the name of the base, with locants. For example, C5H5N—O is named pyridine A-oxide or pyridine 1-oxide. [Pg.32]

Organosulfur Halides. When sulfur is directly linked only to an organic radical and to a halogen atom, the radical name is attached to the word sulfur and the name(s) and number of the halide(s) are stated as a separate word. Alternatively, the name can be formed from R—SOH, a sulfenic acid whose radical prefix is sulfenyl-. For example, CH3CH2—S — Br would be named either ethylsulfur monobromide or ethanesulfenyl bromide. When another principal group is present, a composite prefix is formed from the number and substitutive name(s) of the halogen atoms in front of the syllable thio. For example, BrS—COOH is (bromothio)formic acid. [Pg.38]

Sulfoxides. Sulfoxides, R — SO—R, are named by placing the names of the radicals in alphabetical order before the word sulfoxide. Alternatively, the less senior radical is named followed by sulfinyl- and concluded by the name of the senior group. For example, CH3CH2—SO—CH2CH2CH3 is named either ethyl propyl sulfoxide or l-(ethylsulfinyl)propane. [Pg.38]

Sulfones. Sulfones, R — SO2—R, are named in an analogous manner to sulfoxides, using the word sulfone in place of sulfoxide. In prefixes, the less senior radical is followed by -sulfonyl-. When the > SO2 group is incorporated in a ring, the compound is named as a dioxide. [Pg.38]


See other pages where Grouping words is mentioned: [Pg.115]    [Pg.114]    [Pg.115]    [Pg.114]    [Pg.105]    [Pg.976]    [Pg.332]    [Pg.561]    [Pg.359]    [Pg.343]    [Pg.239]    [Pg.113]    [Pg.8]    [Pg.178]    [Pg.282]    [Pg.666]    [Pg.979]    [Pg.1284]    [Pg.22]    [Pg.33]    [Pg.35]   
See also in sourсe #XX -- [ Pg.50 ]




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