Other Alkyl Derivatives

The crystal structures of the trimercurated acetic acid derivatives, [Hg(H20Hg)(ON02Hg)CC02)N03 (21) and [(02N0Hg)3CC02H].JHN03 (22) have been determined. The cation of (21) consists of Infinite chains of monomers linked through C-Hg-0 connections in contrast, (22) exists as discrete molecules.  

In e-diketone complexes, [RC(0)CR C(0)R] HgX,mercury is bound to carbon, even if 

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The reaction works well with primary alkyl halides, especially with allylic and benzylic halides, as well as other alkyl derivatives with good leaving groups. Secondary alkyl halides give poor yields. Tertiary alkyl halides react under the usual reaction conditions by elimination of HX only. Nitriles from tertiary alkyl halides can however be obtained by reaction with trimethylsilyl cyanide 4 ... 

Alkyl azides are conveniently prepared from the reaction of alkali metal azides with an alkyl halide, tosylate, mesylate, nitrate ester or any other alkyl derivative containing a good leaving group. Reactions usually work well for primary and secondary alkyl substrates and are best conducted in polar aprotic solvents like DMF and DMSO. The synthesis and chemistry of azido compounds is the subject of a functional group series. ... 

Nucleophilic substitutions are especially important for alkyl halides, but they should not be considered to be confined to alkyl halides. Many other alkyl derivatives such as alcohols, ethers, esters, and onium ions 3 also can undergo SN reactions if conditions are appropriate. The scope of SN reactions is so broad that it is impossible to include all the various alkyl compounds and nucleophiles that react in this manner. Rather we shall approach the subject here through consideration of the mechanisms of SN reactions, and then develop the scope of the reactions in later chapters. 

It is possible to prepare esters of phenols with carboxylic acid anhydrides or acid halides, and phenyl ethers by reaction of benzenolate anion with halides, sulfate esters, sulfonates, or other alkyl derivatives that react well by the SN2 mechanism ... 

Attempts to correlate the position of the substituent with the UV spectrum have been largely unsuccessful, but some general comments may be made. The spectra of most monosubstituted derivatives resemble that of benzo [6]thiophene and the three distinct zones usually remain. Methyl or halo substituents cause an overall bathochromic shift relative to benzo [6]thiophene—zone B is most affected by 3-, 5-, or 6-substituents zone C by 5-substituents.134,159,162 3-Alkyl-benzo[6]thiophenes are characterized by zone-B bands of lower intensity than those of benzo [6]thiophene and its other alkyl derivatives.134 The UV spectra of 2-methylbenzo[6]thiophene and its selenium analog have been compared.182... 

The nomenclature of the acyclic hydrocarbons can be readily systematized by naming them in the same manner as other unsaturated aliphatic hydrocarbons (7,42). Hydro derivatives as well as methyl or other alkylated derivatives of the acyclics can be named systematically similarly to the hydrocarbons, and the system can be applied readily to derivatives containing functional groups. 

Contrary to the easy synthesis of alkylated phenols, e.g. via the electrophilic alkylations of phenols using alkyl halides, alkenes or other alkyl derivatives, there is no universal method for the preparation of arylated phenols. Radical or other arylation procedures usually lead to a mixture of difficult to separate isomers. Aryl-substituted phenols have, therefore, to be prepared by special routes. 

Ouweland et al., 1978) or directly by the pyrolysis of amino acids (Fujimaki et al., 1969). Another important, if not the main, precursor of pyridines in roasted coffee is trigonelline (see Section 2.1.1.2), a product isolated by Goi ter (1910), identical to the product isolated from the seeds of Trigonella foenum-graecum. Viani and Horman (1974, 1976) identified 12 pyridinic compounds after pyrolysis of trigonelline, six of which have now been identified in roasted coffee (4-methylpyridine is noted as identified in coffee, but it is not present in the lists of quoted publications, and to our knowledge its identification has not yet been reported in the literature). The presence of four other alkyl derivatives and of two N-methylnicotinamides have not yet been confirmed in the flavor. The authors have also isolated two piperidylpyridines, 3-phenylpyridine and two of its methyl derivatives, as well as four unsubstituted and dimethyl-substituted dipyridyl compounds. 

The energy barriers in the chair-chair inversion of hexahydro-1,3,5-trimethyl-1,3,5-triazine and several other alkyl derivatives (57, R = Me, Et, i-Pr, t-Bu) have been examined. The authors of the latter paper conclude that since AG is solvent independent, the observed effect is due to ring inversion and not inversion of the alkyl substituents on nitrogen. The former authors also examined hexa-methyl-l,3,5-trithiane (58) and s-trioxane (59). Ring inversion of 1,3-dimethyl- (60, R = Me) and 1,3-diethylhexahydropyrimidines (60, R = Et) has been studied by line-shape analysis at low temperatures. 

Understandably, metal complexes containing alkyl groups that have no hydrogen atoms in the fi position, such as methyl, benzyl, and neopentyl, are more stable than other alkyl derivatives. The decomposition of metal alkyls — the reverse of olefin insertion — is of importance in the transition metal catalyzed isomerization of olefins and as a chain-termination reaction in olefin polymerization. The a elimination reaction should also be mentioned here. It is mainly of importance in W and Mo complexes [Til]. Extraction of an a hydrogen atom from methyl compoimds leads to intermediate alkylidene species ... 

As mentioned above, the addition of different trapping reagents diverts the formation of ketone and alcohol giving other alkyl derivatives in similar yields to that of the oxygenation process -. This data proves that the reaction pathway includes an intermediate A, which is a precursor of intermediate B Al. 

In (6.267) the by-prodnct ethyl bromide may compete with the butyl bromide to form some EtPO (OEO2. Other alkyl derivatives such as dialkyl sulphates or alkyl p-toluene sulphonates may also be used for this reaction. 

Other alkylcobalt and alkyltitanium compounds, especially those with branched alkyl substituents, also decompose by olefin elimination. The isobutyl complex, [(CH3)2CHCH2Co(CN)s] , slowly loses isobutene at room temperature (115). The unique stability of methyl derivatives of the transition metals relative to other alkyl derivatives is partly due to the absence of a j8-hydrogen atom which can be transferred to the metal. The... 

Fatty amines and their derivatives represent the most important nitrogen compounds of fatty acids. They possess great ionization constants compared with other alkyl derivatives of ammonia. They are cationic, basic, biologically active, and strongly adsorbed on many surfaces due to their high adsorption potential. They are indispensable in many surface-related physicochemical processes. They are the starting materials for the manufacture of quaternary ammonium compounds and various cationic and amphoteric substances. 

Simple alkyl derivatives of 1 have been reported and studied [56,108-111]. A 1990 patent reports the synthesis of 5-dodecylbenzo[c]thiophene by the sulfoxide route (see Schemes 1 and 2) and its electrochemical polymerization (acetonitrile/Bu4N Cl ) to poly(5-dode-cylbenzo[c]thiophene) (71). The polymer was reported to be soluble in a variety of organic solvents, and an electrochemically doped Him had a four-point probe conductivity of 10 S/cm. Several other alkyl derivatives were said to have been made, and the following conductivities ([Pg.290]

Elimination of haloalkanes (and other alkyl derivatives) may follow the Saytzev rule (nonbulky base, internal alkene formation) or the Hofmann rnle (bulky base, terminal alkene formation). Trans alkenes as products predominate over cis alkenes. Elimination is stereospecific, as dictated by the anti transition state. 

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