2-Methylpropane carbon

Primary alkyl chlorides are fairly stable to fluorine displacement. When fluorinated, 1-chloropropane is converted to 1-chloroheptafluoropropane and 1-chloto-2-methylbutane produces 39% l-chlorononafluoro-2-methylbutane and 19% perfluoro-2-methylbutane. Secondary and tertiary alkyl chlorides can undergo 1,2-chlorine shifts to afford perfluonnated primary alkyl chlorides 2-Chloro-2-methylpropane gives l-chlorononafluoro-2-methylpropane, and three products are obtained by the fluorination of 3-chloropentane [7] (equation 1). Aerosol fluorina-tion of dichloromethane produces dichlorodifluoromethane which is isolated in 98% purity [4 (equation 2). If the molecule contains only carbon and halogens, the picture is different. Molecular beam analysis has shown that the reaction of fluorine with carbon tetrachlonde, lodotrichloromethane, or bromotrichloromethane proceeds first by abstraction of halogen to form a trichloromethyl radical [5]... 

Compounds like butane and pentane, whose carbons are all connected in a row, are called straight-chain alkanes, or normal alkanes. Compounds like 2-methylpropane (isobutane), 2-methylbutane, and 2,2-dimethylpropane, whose carbon chains branch, are called branched-chain alkanes. The difference between the two is that you can draw a line connecting all the carbons of a straight-chain alkane without retracing your path or lifting your pencil from... 

Before beginning a detailed discussion of alkene reactions, let s review briefly some conclusions from the previous chapter. We said in Section 5.5 that alkenes behave as nucleophiles (Lewis bases) in polar reactions. The carbon-carbon double bond is electron-rich and can donate a pair of electrons to an electrophile (Lewis acid), for example, reaction of 2-methylpropene with HBr yields 2-bromo-2-methylpropane. A careful study of this and similar reactions by Christopher Ingold and others in the 1930s led to the generally accepted mechanism shown in Figure 6.7 for electrophilic addition reactions. 

El eliminations begin with the same uni molecular dissociation we saw in the Sfsjl reaction, but the dissociation is followed by loss of H+ from the adjacent carbon rather than by substitution. In fact, the El and SN1 reactions normally occur together whenever an alkyl halide is treated in a protic solvent with a non-basic nucleophile. Thus, the best El substrates are also the best SN1 substrates, and mixtures of substitution and elimination products are usually obtained. For example, when 2-chloro-2-methylpropane is warmed to 65 °C in 80% aqueous ethanol, a 64 36 mixture of 2-methyl-2-propanol (Sjql) and 2-methylpropene (El) results. 

One of the most striking differences between conjugated dienes and typical alkenes is in their electrophilic addition reactions. To review briefly, the addition of an electrophile to a carbon-carbon double bond is a general reaction of alkenes (Section 6.7). Markovnikov regiochemistry is found because the more stable carbo-cation is formed as an intermediate. Thus, addition of HC1 to 2-methylpropene yields 2-chloro-2-methylpropane rather than l-chloro-2-methylpropane, and addition of 2 mol equiv of HC1 to the nonconjugated diene 1,4-pentadiene yields 2,4-dichloropentane. 

Two different alkanes are known with the molecular formula C Hm- In one of these, called butane, the four carbon atoms are linked in a straight (unbranched) chain. In the other, called 2-methylpropane, there is a branched chain. The longest chain in the molecule contains three carbon atoms there is a CH3 branch from the central carbon atom. The geometries of these molecules are shown in Figure 22.2 (p. 581). The structures are... 

With C4H 0, we find another reason for the variety of compounds that carbon can form the same atoms can bond together in different arrangements. Four carbon atoms can link together in a chain to form butane (17) or in a Y-shape to form methylpropane (18). As we saw in Section 16.7, different compounds with... 

Building on propane, we can replace a hydrogen atom on a terminal carbon with a methyl group to form butane, an alkane with four carbon atoms in a row. Alternatively, we can replace either hydrogen atom on the inner carbon of propane to give a different compound, 2-methylpropane. In this molecule, three carbon atoms are in a row, but the fourth carbon atom is off to one side. 

Carbon tetrachloride, 0322 Carbon tetrafluoride, 0349 Carbon tetraiodide, 0525 f 1-Chlorobutane, 1637 f 2-Chlorobutane, 1638 f Chlorocyclopentane, 1923 f l-Chloro-l,l-dilluoroethane, 0731 Chlorodilluoromethane, 0369 f Chloroethane, 0848 Chloroform, 0372 f Chloromethane, 0432 f l-Chloro-3-methylbutane, 1986 f 2-Chloro-2-methylbutane, 1987 f Chloromethyl ethyl ether, 1246 f Chloromethyl methyl ether, 0850 f l-Chloro-2-methylpropane, 1639 f 2-Chloro-2-methylpropane, 1640 f 1-Chloropentane, 1988 f 1-Chloropropane, 1243 f 2-Chloropropane, 1244 f l-Chloro-3,3,3-trifluoropropane, 1127 1,2-Dibromoethane, 0785 Dibromomethane, 0395... 

Chemical/Physical. Complete combustion in air produces carbon dioxide and water vapor. 2-Methylpropane will not hydrolyze because it does not contain a hydrolyzable functional group. 

Photolytic. Products identified from the photoirradiation of 2-methylpropene with nitrogen dioxide in air are 2-butanone, 2-methylpropanal, acetone, carbon monoxide, carbon dioxide, methanol, methyl nitrate, and nitric acid (Takeuchi et al., 1983). Similarly, products identified from the reaction of 2-methylpropene with ozone included acetone, formaldehyde, methanol, carbon monoxide, carbon dioxide, and methane (Tuazon et al., 1997). 

The first strnctnre has the carbon atoms arranged in a linear fashion and is called normal butane or, simply, n-bntane. The second has a branched structure and is termed tTobntane (or, more rigoronsly, 2-methylpropane). 

Aliphatic nitro compounds with the nitro group on a tertiary carbon were reduced to amines with aluminum amalgam [146 or iron [559]. 2-Nitro-2-methylpropane afforded ferf-butylamine in 65-75% yield [146. Even some secondary nitroalkanes were hydrogenated to amines. fra s-l,4-Dinitrocy-clohexane was converted to frans-l,4-diaminocyclohexane with retention of configuration. This may be considered as an evidence that the intermediate nitroso compound is reduced directly and not after tautomerization to the isonitroso compound [560] (see Scheme 54). 

The aldehydes 2-methylpropanal, 2-methylbutanal, 3-methylbutanal, methional, and phenylacetaldehyde are so-called Strecker aldehydes, formed as a result of a reaction between dicarbonyl products of the Amadori pathway and amino acids, having one less carbon atom than the amino acid (i). 

A similar conclusion applies to a Mg-V-O catalyst in which Mg3(V04)2 is the active component. The relative rates of reaction for different alkanes on this catalyst follow the order ethane < propane < butane 2-methylpropane < cyclohexane (Table I) [12-14]. This order parallels the order of the strength of C-H bonds present in the molecule, which is primary C-H > secondary C-H > tertiary C-H. Ethane, which contains only primary C-H bonds, reacts the slowest, whereas propane, butane, and cyclohexane react faster with rates related to the number of secondary carbon atoms in the molecule, and 2-methylpropane, with only one tertiary carbon and the rest primary carbons, reacts faster than propane which contains only one secondary carbon. Similar to a Mg-V-O catalyst, the relative rates of oxidation of light alkanes on a Mg2V207 catalyst follow the same order (Table I). 

Amino-2-methylpropane, Methylene chloride, 1,3,5-Trifluoro-2,4,6-trinitrobenzene, Potassium hydrogen carbonate, Trifluoroacetic acid, Cyanotrimethylsilane, Nitromethane, Acetonitrile, Sulfuric acid... 

The products from the partial fluorinations of butane32 and 2-methylpropane33 over cobalt(lll) fluoride are even more complex, 51 and 27 compounds, respectively, being identified. Most are C4F H10 n isomers which retained the original carbon skeletons, but up to 2% in each case has the carbon skeleton of the isomer (i.e., 2-methylpropane fluorination yields ca. 2% of products with the butane skeleton). From butane, at 140-230 C, only two compounds are present as more than 10% of the reaction product, 1 //,3//-octafluorobutane (11%) and 1 //,27f,4//-heptafluorobutane (14%). 2-Methylpropane is similar, at 140- 200°C only four compounds are present as over 10% of the product 2-(difluoromethyl)-l,1,1,2,3-pentafluoro-propane (14%), 2-(difluoromethyl)-l,l,2,3,3-pentafluoropropane (16%), 1,1,2,3,3-pentafluo-ro-2-(fluoromethyl)propane (24%), and l,l,2,3-tetrafluoro-2-(fluoromethyl)propane (15%). 

The first step of the activation of butane and cyclohexane has been assumed to be the cleavage of a secondary C—H bond, with minor contributions from primary C — H bonds in the case of butane. This picture is supported only by indirect evidence. When the relative rates of reaction of various alkanes were compared on a V-Mg oxide and Mg2V207 catalyst (Table VIII), it was found that alkanes with only primary carbons (ethane) reacted most slowly. Those with secondary carbons (propane, butane, and cyclohexane) reacted faster, with the rate being faster for those with more secondary carbon atoms. Finally, the alkane with one tertiary carbon (2-methylpropane) reacted faster than the ones with either a single or no secondary carbon (26). From these data, it was estimated that the relative rates of reaction of a primary, secondary, and tertiary C—H bond in alkanes on the V-Mg oxide catalyst were 1, 6, and 32, respectively (26). 

SAMPLE SOLUTION (a) There are two C4H10 isomers. Butane (see Table 2.2) is the IUPAC name for the isomer that has an unbranched carbon chain. The other isomer has three carbons in its longest continuous chain with a methyl branch at the central carbon its IUPAC name is 2-methylpropane. 

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