Naming systems ketones

Like aldehydes, ketones can be named using either the common system or the IUPAC system. In the common system, ketones names are created by naming the groups attached to the carbonyl carbon and then adding the word ketone. Following are several examples ... 

Carotenoids that contain an oxygenated functionality are collectively referred to as xanthophylls. They retain the systematic naming system of carotenes, with the additional functionalities named according to the usual nomenclature rules previously discussed. For example, p,P-carotene-3,3 -diol (zeaxanthin) (Figure 3.10a). Methoxy, carboxy, aldehyde, epoxy, and ketone derivates are also common. 

There are two series of simple monosaccharides aldoses, which contain an aldehyde group, and ketoses, which contain a ketone group. Simple monosaccharides are also classified by the munber of carbon atoms which they contain e.g., trioses (3 C), tetroses (4 C), pentoses (5 C), and hexoses (6 C). The two naming systems are combined e.g., glucose is an aldohexose as it is a six-carbon monosaccharide with an aldehyde group. 

In the lUPAC system, the ending for ketones is -one (from the last syllable of ketone). The chain is numbered so that the carbonyl carbon has the lowest possible number. Common names of ketones are formed by adding the word ketone to the names of... 

In the lUPAC system, ketones are named by selecting as the parent alkane the longest chain that contains the carbonyl group and then indicating its presence by... 

However, two complications call for care. (XVI) is pyridine-2(lH),4(3JT)-dione, and (XVII) is pyridine-2,3-dione, the disparity in the degrees of hydrogenation being indicated only by the H s. Also there are long-established names for ketones in some simple five-membered heterocycUc systems that refer to a wrong stage of hydrogenation an example of this is 5-pyrazolone (X II). Such names have to be accepted so also have the abbreviated names such as pyridone, quinolone, isoquinolone, and acridone. 

The lUPAC naming system for ketones uses the suffix -one. The parent chain must include the carbonyl group and be numbered from the end of the... 

A few of the common names acceptable for ketones m the lUPAC system are... 

Later, in a modification to the above system, we reported the use of an indenylruthenium complex 2 as a racemization catalyst for the DKR of secondary alcohols, which does not require ketones but a weak base hke triethylamine and molecular oxygen to be achvated. The DKR with 2 in combination with immobilized Pseudomonas cepacia lipase (PCL, trade name. Lipase PS-C ) was carried out at a lower temperature (60°C) and provided good yields and high optical purities (Table 2). This paved the way for the omission of ketones as... 

Addition of triethylamine to the oxazaborolidine reaction system can significantly increase the enantioselectivity, especially in dialkyl ketone reductions.79 In 1987, Corey et al.80 reported that the diphenyl derivatives of 79a afford excellent enantioselectivity (>95%) in the asymmetric catalytic reduction of various ketones. This oxazaborolidine-type catalyst was named the CBS system based on the authors names (Corey, Bakshi, and Shibata). Soon after, Corey s group81 reported that another fi-methyl oxazaborolidine 79b (Fig. 6-6) was easier to prepare and to handle. The enantioselectivity of the 79b-catalyzed reaction is comparable with that of the reaction mediated by 79a (Scheme 6-36).81 The -naphthyl derivative 82 also affords high enantioselectivity.78 As a general procedure, oxazaborolidine catalysts may be used in 5-10 mol%... 

In the early 1980 s Julia and Colonna published a series of papers which, to some extent, filled the gap left by the natural biocatalysts. The Spanish and Italian collaborators showed that a, -unsaturated ketones of type 1 underwent asymmetric oxidation to give the epoxide 2 using a three-phase system, namely aqueous hydrogen peroxide containing sodium hydroxide, an organic solvent such as tetrachloromethane and insoluble poly-(l)-alanine, (Scheme 1) [12]. The reaction takes place via a Michael-type addition of peroxide anion (the Weitz-Scheffer reaction). 

In what appears to be a particularly irmovative development in the area of UV/ Vis-based ee screening systems, the determination of the enantiomeric purity of chiral alcohols 9 is based on a new concept of using two enantioselective enzymes to modify the product (84). The method allows the determination of ee values independent of the concentration, which may be of significant advantage in directed evolution projects. It can be used in three different biocatalytic processes, namely biohydroxylation of alkanes, reductase-catalyzed reduction of ketones, and lipase-or esterase-catalyzed ester hydrolysis. 

The suffix -one is also used to name classes other than ketones. For instance, the lactones and the lactams, which are heterocyclic systems, can be named by adding the suffix -one to the name of the corresponding heterocycle. Specific suflBxes -olactone and -olactam may also be used in simple cases. 

Common names use the names of R or Ar as separate words, along with the word ketone. The lUPAC system replaces the -e of the name of the longest chain by the suffix -one. 

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