Amides ketones

The industrial process for preparing the reagent usually permits a little hydrolysis to occur, and the product may contain a little free calcium hydroxide or basic chloride. It cannot therefore be employed for drying acids or acidic liquids. Calcium chloride combines with alcohols, phenols, amines, amino-acids, amides, ketones, and some aldehydes and esters, and thus cannot be used with these classes of compounds. 

Me3SiI, CH2CI2, 25°, 15 min, 85-95% yield.Under these cleavage conditions i,3-dithiolanes, alkyl and trimethylsilyl enol ethers, and enol acetates are stable. 1,3-Dioxolanes give complex mixtures. Alcohols, epoxides, trityl, r-butyl, and benzyl ethers and esters are reactive. Most other ethers and esters, amines, amides, ketones, olefins, acetylenes, and halides are expected to be stable. 

As normally polymerized, PVF melts between IH5 and 210 °C and contains 12 18% inverted monomer units ft is normally considered a thermoplastic, but because of its instability above its melting point, it cannot be processed by conventional thermoplastic techniques Instead it is generally extruded into films in a solvent swollen (organosol) form and the solvent is subsequently evaporated and recovered Such films can be onented further to achieve specific mechanical properties PVF films are exceptionally weather and radiabon resistant considenng their modest fluonne content PVF is insoluble below 100 °C but, at higher temperatures, it dissolves in polar solvents like amides, ketones, tetramethylene sulfone, and tetramethylurea Resistance to acids and bases at room temperature IS good [1, 29 ... 

Rhodium precipitation in solubilized rhodium-phosphite complex catalyzed liquid recycle hydroformylation may be minimized or prevented by carrying out product recovery in the presence of an organic polymer containing polar functional groups such as amides, ketones, carbamates, ureas and carbonates.[20] Patent examples include the use of polyvinylpyrrolidone and vinylpyrrolidone-vinyl acetate copolymer with diorganophosphite-modified rhodium catalysts. 

The mere presence of a polar functional group (ester, amide, ketone, ether, sulfonamide, urethane, etc.) seems to be a fundamental requirement for smooth macrocyclizations by RCM. The two examples displayed in Scheme 14 nicely illustrate this aspect. 

The reactivity of heterocyclic systems with carbenes, generated under phase-transfer catalytic conditions, has been reviewed for the period up to 1983 [1]. Most unsaturated non-heteroaromatic systems react with carbenes in the manner expected of alkenes, amines, amides, ketones, etc. (see Sections 7.3,7.5 and 7.6). 

Carbonyl carbons, such as those in esters, carboxylic acids, amides, ketones and aldehydes, in which the sp carbon is bonded by a ir-bond to the highly electronegative O, have a characteristic chemical shift of S 160-220 (Box 4.13). Within this range, the sp carbon atoms of aldehydes and ketones are most deshielded and usually resonate at 8 185-220, while those of carboxylic acids and their derivatives resonate about 160-180. 

Carboxylic acids are generally attached to polymeric supports as esters or amides. Depending on the type of linker and on the cleavage conditions used, cleavage can lead either to the regeneration of a carboxylic acid, or to the formation of a new product, such as an ester, amide, ketone, or alcohol. This section covers only linkers which lead, upon cleavage, to the release of carboxylic acids. 

By contrast, the similar phosphate-phosphonate rearrangement proceeds with retention, whether it proceeds via a tertiary56 or a secondary57 organolithium 57 or 58, as does the related amide-ketone rearrangement of 59.58 These retentive rearrangements presumably involve C=0-Li or P=0-Li coordination not possible in the Brook rearrangement. 

There is qualified support for the weak-acid hypothesis, particularly for compounds such as 2,4-dichlorophenoxyacetic acid. Crisp and Look (.5) compared the phloem mobility of several synthetic 4-chlorophenoxy derivatives. The carboxyl derivative was loaded and transported in the phloem, whereas derivatives in which the COOH group was replaced by an ethyl ester, amide, ketone, alcohol, or amino group were not translocated. 

Synthesis of Fluorinated Carboxylic Acids, Esters, Amides, Ketones, and Alcohols through Halogen Exchange... 

Oximes Amides Ketones Aldehydes Ethers Esters... 

The selective reduction of the primary halides can also be accomplished with NaCNBH3 in HMPA or DMSO or even by NaBH4 in warm DMSO. Epoxides, nitriles, amides, ketones, and esters are not affected under these conditions [HKl, LI], as illustrated in Figure 2.4. n-Bu4NCNBH3 or resin-supported cya-noborohydride is even more selective, since each reduces only the primary iodides and bromides, leaving the chlorides unchanged [HN3]. 

In addition to heterocycles that were successfully arylated under first-generation procedure, the reaction scope is broadened to include bis(aryl)imidazoles and triazoles, but benzothiazole was found to be incompatible. As previously observed, 3,4-dihydroquinazoline is a reactive coupling partner but only the dehydrogenated product 2-arylquinazoline is obtained. Furthermore, in addition to iodoarenes, bro-moarenes are reactive under these reaction conditions. The reaction is tolerant of a large number of functional groups and haloarene substituents, including nitrile, chloro, primary amide, ketone, and ester. Both electron-poor and electron-rich bro-moarenes showed good reactivity. Both para- and meta-substituents were well tolerated, but ortao-substituents (OMe, CF3) shut down the reaction. 

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