Saturated compounds, reaction

Tlie bifunctional sulfenyl chloride 213 was obtained by chlorination of 144 in good yield, although excessive chlorination led to the saturated compound 214 (94CB533). A series of compounds 215-220 were obtained from 213 by reactions with secondary amines ferf-butyl methyl ketone hexane-2,4-dione 2,6-dimethylcyclohexanone diethyl malonate and acetylacetone, respectively. 

The reactivity of a remarkable electronically unsaturated tantalum methyli-dene complex, [p-MeCgH4C(NSiMe3)2]2Ta( = CH2)CH3, has been investigated. Electrophilic addition and olefination reactions of the Ta = CH2 functionality were reported. The alkylidene complex participates in group-transfer reactions not observed in sterically similar but electronically saturated analogs. Reactions with substrates containing unsaturated C-X (X = C, N, O) bonds yield [Ta] = X compounds and vinylated organic products. Scheme 117 shows the reaction with pyridine N-oxide, which leads to formation of a tantalum 0x0 complex. ... 

This dry ozonation procedure is a general method for hydrox-ylation of tertiary carbon atoms in saturated compounds (Table 1). The substitution reaction occurs with predominant retention of configuration. Thus cis-decalin gives the cis-l-decalol, whereas cis- and frans-l,4-dimethylcyclohexane afford cis- and trans-1,4-dimethylcyclohexanol, respectively. The amount of epimeric alcohol formed in these ozonation reactions is usually less than 1%. The tertiary alcohols may be further oxidized to diols by repeating the ozonation however, the yields in these reactions are poorer. For instance, 1-adamantanol is oxidized to 1,3-adamantane-diol in 43% yield. Secondary alcohols are converted to the corresponding ketone. This method has been employed for the hydroxylation of tertiary positions in saturated acetates and bromides. 

Their physical properties are essentially those of the alkanes. It is the unsaturated linkages that dominate the chemistry and the main reaction is one of addition (e.g. hydrogen, halogen, and hydrogen halides) across the double bond to produce saturated compounds. This reactivity is utilized in the manufacture of long-chain polymers, e.g. polyethylene and polypropylene. 

The frontier-electron density was used for discussing the reactivity within a molecule, while the superdelocalizability was employed in comparing the reactivity of different molecules 44>. Afterwards, the applicability of the frontier-electron theory was extended to saturated compounds 50>. The new theoretical quantity "delocalizability was introduced for discussing the reactivity of saturated molecules 60>. These indices satisfactorily reflected experimental results of various chemical reactions. In addition to this, the conspicuous behavior of HO and LU in determining the steric course of organic reactions was disclosed 44.51). 

Scheme 5.11 Reaction routes for various saturated and unsaturated carboxylic acids and alcohols using a rhodium catalyst and a lipase. s-g indicates sol-gel encapsulation of the catalyst superscript u and s indicate unsaturated and saturated compounds,...

One facet of the whole cell work that draws attention is the sometimes profitable operation of a cascade of reactions in the multi-enzyme portfolio of the microorganism. For instance (Scheme 11), the allylic alcohol (14) is reduced to the corresponding saturated compound in high yield and optical purity (though in a slow reaction) via the intermediacy of the corresponding enal and (S)-2-benzyloxymethylpropanal[531. 

Metabolism of unsaturated fatty acids is similar to that of the saturated compounds just described, but additional enzymic reactions are necessary. 

The hydrogenation reaction is possible only for compounds with double or triple bonds, and such compounds are said to be unsaturated. The addition of the hydrogen to the carbon atoms that were double- or triple-bonded converts the unsaturated compound to a saturated compound with only single bonds. 

Synthesis of 2,3-dihydro-l,4-dithiin 11 was accomplished from l,3-dithiol-2-one 247 in the presence of dibro-moethane and potassium hydroxide <1998JOG3952>, while reaction of 2,3-dichloro-l,4-dioxane with powdered Zn in hexamethylphosphoramide (HMPA) was used for the synthesis of 1,4-dioxene 10 <1998JPP10067773>. To obtain substituted 1,4-oxathianes, the hydrogenation of the corresponding partially saturated compounds has been employed <2001J(P1)2604>. 

The radical so formed is apparently stable, for it can be kept both in solution and in the dry crystalline state for weeks. The radical refuses to unite with another one of its kind, and thus forms a distinct exception to all similar reactions. It might be said that, perhaps, it does polymerize to hexaphenylethane, (C6Hs)3C—C(QH5)3, but this hydrocarbon is so unstable that mere exposure to air is sufficient to break it down. Such an assumption seems to me less tenable than that of a free radical. Hexaphenylethane must, according to all our present notions of valence, be a saturated compound. 

In reactions with organic compounds, the acid may act not only as an oxidizer (see above) but also as a chlorinating agent (in the case of saturated compounds) or the addition of HO-C1 to the double linkage C=C to form a chlorhydrin ... 

The insertion reaction is usually more complicated than equation (1) would indicate. The evidence now available suggests that M-X must be coordinately unsaturated in order to react with Y. Therefore, before the insertion reaction can occur, a preliminary step is often required to form M-Z from a coordinately saturated species. Furthermore, the insertion reaction may not go to completion or may not even go at all, unless there is another ligand molecule present to form a stable, coordinately saturated compound from M-Y-Z as the final product. 

Reactions with Saturated Compounds Including Ones with Substituents... 

As to the interaction between hydroxyl and saturated compounds, the reaction of OH with propane shows22 that the basic hydroxyl reaction is that yielding water... 

Some conclusions on the reaction mechanism may be drawn from the rate constants obtained. It was shown for hydroxyl reactions with saturated compounds (propane, for example) that the main reaction of OH was the hydrogen atom abstraction in the formation of water. This is an accepted point of view. However, another route is possible for reactions with unsaturated hydrocarbons, i.e., addition at the double bond. This is the case for the H atom with saturated compounds H reacts by abstraction, and with unsaturated ones by addition. 

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