Structure straight-chained

Strategy Start with the straight-chain structure, stringing all five carbon atoms one after the other. Then work with structures containing four carbon atoms in a chain with one branch find all the nonequivalent structures of this type. Continue this process using a three-caibon chain, which is the shortest one that can be drawn for C5H12. 

Selectivity to desired products including light hydrocarbons, gasoline, or diesel fuel depends upon the catalyst employed, the reactor temperature, and the type of process employed. Products of the F-T synthesis are suitable for further chemical processing because of their predominantly straight chain structure and the position of the double bond at the end of the chain. By-products formed on a lesser scale include alcohols, ketones, acids, esters, and aromatics. 

Figure 1.10 Examples of the cyclic and straight chain structures of monosaccharides. The carbon of the carbonyl group has the lowest locant...

This is the most abundant group of compounds that are classified as lipids. They occur as isolated molecules and are more commonly found as residues in other lipid structures. The fatty acids and residues that are commonly found are normally referred to by trivial names (Table 1.4). They usually have straight chain structures with even numbers of between 14 and 22 carbon atoms inclusive. Both saturated and unsaturated residues are found. In the latter case both cis and trans isomers are known but the cis isomers are more common. A few residues have structures that have side chains and/or other functional groups. 

If all alkanes had unbranched (straight-chain) structures, their nomenclature would be simple. Most alkanes have structural isomers, however, and we need a way of naming all the different isomers. For example, there are two isomers of formula C4H10. The unbranched isomer is simply called butane (or n-butane, meaning normal butane), and the branched isomer is called isobutane, meaning an isomer of butane. ... 

The Fischer projection formula for D-glucose (Example 2.3) is also known as the open- or straight-chain structure. This structure occurs only in solution. There are two crystalline forms of D-glucose, known as a and /3, which also have different optical activities when dissolved. X-ray diffraction studies have confirmed chemical evidence that a- and /3-D-glucose are structures containing a ring of five carbon atoms and one oxygen atom ... 

The ring of a glycoside cannot open to give a straight-chain structure. Consequently, glycosides have no reducing properties. 

A large number of polyacetylenes have retained obviously straight-chain structures and are readily recognized by their typical ultraviolet absorptions (e.g. 1, 2,3,20,22, 31, 32, etc.). 

A number of different dimers and ohgomers are produced from fatty acids and alcohols. These are branched-chain compounds with significantly lower melting points than straight chain structures of similar molecular weight. Fully saturated dimers... 

For the straight-chain structure 2 a higher surface tension but lower interfacial tension... 

Lifshitz-van der Waals portion (/jf). Straight-chain structures improve the chances for intermolecular interactions of the Lifshitz-van der Waals type [13], On the other hand we assume that only one of the two oxygen atoms of the straight-chain trisiloxanyl moiety is sufficiently close to the water surface to influence the donor-acceptor portion. As to expect from the results for pure liquids only donor-acceptor portions fj/ were detected at the interface solid/liquid. The values are identical to those for indicating a common source for the donor-acceptor portions The increased y l value for the branched structure 3 indicates that in this particular case both oxygen atoms are exposed to the perfluorinated surface. 

The straight-chain structure of D-glucose and the interconversion to the two cyclic anomers are shown on the right. 

We first write the carbon skeleton of the straight-chain isomer (no branching). Then we remove one carbon from the straight-chain structure and reposition it to form the skeleton for a branched isomer. We check to see whether branching is possible at other carbon atoms. Then... 

Furthermore, it is also noted that the interlayer distance of the PCN is related to the intrinsic polymer structure, such that the PEO molecule exhibits a straight chain structure and has high backbone flexibility because of the backbone oxygen atom. Also, the minimum thickness required to accommodate this polymer is much smaller than the minimum layerthickness required for accommodating bulky PMMA molecules. 

Various structures have been proposed for the glycosyl ureides, but these may be resolved into two alternative forms the straight-chain structure as advanced by Schoorl (XXXIX) and the cyclic form as proposed by Hynd and Macfarlane, Helferich and Kosche (VIII), and others. 

Monosaccharides can have both cyclic and straight chain structures. Cyclomonosaccharides are formed when straight-chain monosaccharides are dissolved in water. In this case, the number of asymmetrical carbon atoms increases to five. This process is known as hemiacetal formation. Let us examine the formation of the cyclic structure in the glucose molecule. 

Answer For small hydrocarbon molecules (eight or fewer carbon atoms), it is relatively easy to determine the number of stmctural isomers by trial and error. The first step is to write down the straight-chain structure ... 

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