Functional groups, organic aldehyde

Aldehydes and ketones both have the carbonyl functional group. An aldehyde is an organic compound that has a double-bonded oxygen on the last carbon of a carbon chain. The functional group for an aldehyde is... 

Because monosaccharides contain alcohol functional groups and aldehyde (or ketone) functional groups, the reactions of monosaccharides are an extension of what you have already learned about the reactions of alcohols, aldehydes, and ketones. For example, an aldehyde group in a monosaccharide can be oxidized or reduced and can react with nucleophiles to formimines, hemiacetals, and acetals. When you read the sections that deal with the reactions of monosaccharides, you will find cross-references to the sections in which the same reactivity for simple organic compounds is discussed. As you study, refer back to these sections they will make learning about carbohydrates a lot easier and will give you a good review of some chemistry that you have already learned about. 

Functional Groups Organic compounds with similar fxmctional groups form a family of compounds and exhibit similar chemical and physical properties. For example, carboxylic acids behave as acids and therefore have low pH. Many esters, aldehydes, and ketones, especially those that contain an aromatic ring in their R group, tend to have pleasant smells. Amines, on the other hand, tend to have foul smells. 

The oxidation of higher alkenes in organic solvents proceeds under almost neutral conditions, and hence many functional groups such as ester or lac-tone[26,56-59], sulfonate[60], aldehyde[61-63], acetal[60], MOM ether[64], car-bobenzoxy[65], /-allylic alcohol[66], bromide[67,68], tertiary amine[69], and phenylselenide[70] can be tolerated. Partial hydrolysis of THP ether[71] and silyl ethers under certain conditions was reported. Alcohols are oxidized with Pd(II)[72-74] but the oxidation is slower than the oxidation of terminal alkenes and gives no problem when alcohols are used as solvents[75,76]. 

Miscellaneous Curing Reactions. Other functional groups can react with the thiol terminal groups of the polysulfides to cross-link the polymer chains and build molecular weight. For example, aldehydes can form thioacetals and water. Organic and inorganic acids or esters can form thioesters. Active dienes such as diacrylates can add to the thiols (3). Examples of these have been mentioned in the Hterature, but none have achieved... 

An ability to fonn caibon-caibon bonds is fundamental to organic synthesis. The addition of Grignaid reagents to aldehydes and ketones is one of the most frequently used reactions in synthetic organic chemistry. Not only does it pennit the extension of caibon chains, but because the product is an alcohol, a wide variety of subsequent functional group transformations is possible. 

The next several chapters deal with the chemistry of various oxygen-containing functional groups. The interplay of these important classes of compounds—alcohols, ethers, aldehydes, ketones, carboxylic acids, and derivatives of carboxylic acids— is fundfflnental to organic chemistry and biochemistry. 

An example of how information from fragmentation patterns can be used to solve structural problems is given in Worked Example 12.1. This example is a simple one, but the principles used are broadly applicable for organic structure determination by mass spectrometry. We ll see in the next section and in later chapters that specific functional groups, such as alcohols, ketones, aldehydes, and amines, show specific kinds of mass spectral fragmentations that can be interpreted to provide structural information. 

We see from reactions (75) and (79) that oxidation of an aldehyde gives an organic acid. All of these acids contain the functional group —COOH, the carboxyl group. The bonding in this group is as follows ... 

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