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Ester, amide From ketone

Synthesis of glycidic esters (amides) from an aldehyde or ketone and an a-haloester (amide). [Pg.88]

Complete details for synthesis of ( + )- or ( —)-l from (IS)- or (1R)-10-camphor-sulfonic acid in 77% yield are now available. In general, this oxaziridine is less active than other N-sulfonyloxaziridines, but it is the preferred reagent for hydrox-ylation of lithium enolates of esters, amides, and ketones in 30-95% ee.1... [Pg.61]

Oxaziridines. Davis has developed the use of chiral 2-sulfonyloxaziridines derived from camphorsulfonic acid as chiral auxiliaries in the asymmetric oxidation reactions. Although other oxaziridines may be preferable, the camphor-derived oxaziridines can be used for the oxidation of sulfides and disulfides to sulfoxides and thiosulfinates as well as for the epoxidation of alkenes. On the other hand, the camphoryloxaziridines are the preferred reagents for hydroxylation of lithium enolates of esters, amides, and ketones, as utilized in the synthesis of kjellmanianone (eq 17). ... [Pg.174]

An unprecedented protocol for the stereoselective synthesis of stracturally diverse electron-deflcient alkenes in moderate to excellent yields from readily accessible A-sulfonyl imines and stabilized phosphonium ylides has been reported. The oleflna-tion reaction of (V-sulfonyl imines with nitrile-stabilized phosphonium ylides affords an array of a./S-unsaturated nitriles with high Z selectivity, and the reactions with ester-, amide-, and ketone-stabilized phosphonium ylides afford a,)3-unsaturated esters, amides, and ketones with high E selectivity, respectively (Scheme 3). [Pg.366]

In the second group we consider interconversions of functional groups with the exchange of hetereoatoms, breaking of old and formation of new C-heteroatom bonds. Examples of these transformations are interconversion of an amide to ester, thioketone to ketone or alkylhalide to alcohol. They are related to S5mthetic reactions formation of amide from ester, thioketone from ketone or haloalkane from alcohol. Characteristic of all the above interconversions is the disconnection (imaginative process ) of the C-heteroatom bond, C-N or C-O. In the synthetic direction C-N, C-S and C-Hal bonds are formed. Therefore, such FGIs are also denoted as DIS-C-X, where X stands for heteroatom. [Pg.4]

Carboxylic acids may also be prepared by conversion of ketones into esters or amides, followed by hydrolysis. See section 117 (Esters from Ketones) and section 87 (Amides from Ketones)... [Pg.62]

The cyclic tetramer of p-t rf-butylphenol-formaldehyde condensates which maintains a cone-type conformation called a calix[4]arene from its cuplike shape, similar to that of a Greek crater vase, tends to complex with small organic compounds or metal ions. Further, incorporation of carbonyl groups such as ester, amide and ketone linkages into the phenolic oxygen atoms of the calixarene makes it function as an ionophore [1]. [Pg.333]

Lithium enolates from esters, amides, and ketones may be fluorinated with A-fluorobis[(trifluoromethyl)sulfonyl]imide (Eq. 6.58) [91],... [Pg.185]

Carbonylation of enol triflates derived from ketones and aldehydes affords Q,/)-unsaturated esters[332]. Steroidal esters are produced via their aryl and enol triflates[328]. The enol triflate in 477 is more reactive than the aryl tritlate and the carbonylation proceeds stepwise. First, carbonylation of the enol triflate affords the amide 478 and then the ester 479 is obtained in DMSO using dppp[333]. [Pg.193]

The palladium-catalyzed carbonylation of aryl halides in the presence of various nucleophiles is a convenient method for synthesizing various aromatic carbonyl compounds (e.g., acids, esters, amides, thioesters, aldehydes, and ketones). Aromatic acids bearing different aromatic fragments and having various substituents on the benzene ring have been prepared from aryl iodides at room temperature under 1 atm... [Pg.184]

Low-coordinate species of the main group elements of the second row such as carbenes, olefins, carbonyl compounds (ketones, aldehydes, esters, amides, etc.), aromatic compounds, and azo compounds play very important roles in organic chemistry. Although extensive studies have been devoted to these species not only from the physical organic point of view but also from the standpoints of synthetic chemistry and materials science, the heavier element homologues of these low-coordinate species have been postulated in many reactions only as reactive intermediates, and their chemistry has been undeveloped most probably due to... [Pg.121]

The ruthenium carbene catalysts 1 developed by Grubbs are distinguished by an exceptional tolerance towards polar functional groups [3]. Although generalizations are difficult and further experimental data are necessary in order to obtain a fully comprehensive picture, some trends may be deduced from the literature reports. Thus, many examples indicate that ethers, silyl ethers, acetals, esters, amides, carbamates, sulfonamides, silanes and various heterocyclic entities do not disturb. Moreover, ketones and even aldehyde functions are compatible, in contrast to reactions catalyzed by the molybdenum alkylidene complex 24 which is known to react with these groups under certain conditions [26]. Even unprotected alcohols and free carboxylic acids seem to be tolerated by 1. It should also be emphasized that the sensitivity of 1 toward the substitution pattern of alkenes outlined above usually leaves pre-existing di-, tri- and tetrasubstituted double bonds in the substrates unaffected. A nice example that illustrates many of these features is the clean dimerization of FK-506 45 to compound 46 reported by Schreiber et al. (Scheme 12) [27]. [Pg.60]

The anions of primary nitramines, like other nucleophiles, can undergo Michael 1,4-addition reactions with a range of a,-unsaturated substrates to form secondary nitramines of varying molecular complexity (Equation 5.18). Kissinger and Schwartz prepared a number of secondary nitramines from the condensation of primary nitramines with a,/3-unsaturated ketones, esters, amides and cyanides. In a standard experiment a solution of the primary nitramine and... [Pg.234]

A chiral auxiliary must be easily obtained from the chiral carbon pool generally alcohols or amines are used, since they can be readily covalently bound to substrates e.g., carboxylic acids27, ketones or aldehydes in the form of esters, amides, ketals. or imino-derivatives. [Pg.122]


See other pages where Ester, amide From ketone is mentioned: [Pg.77]    [Pg.1143]    [Pg.591]    [Pg.87]    [Pg.1216]    [Pg.12]    [Pg.1216]    [Pg.508]    [Pg.308]    [Pg.27]    [Pg.36]    [Pg.258]    [Pg.1029]    [Pg.4]    [Pg.238]    [Pg.35]    [Pg.447]    [Pg.402]    [Pg.201]    [Pg.125]    [Pg.125]    [Pg.35]    [Pg.211]    [Pg.125]    [Pg.258]    [Pg.99]   
See also in sourсe #XX -- [ Pg.20 ]

See also in sourсe #XX -- [ Pg.20 ]




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Amidation, esters

Amide-esters => ketones

Amides from esters

Amides from ketones

Amides ketones

Esters amides

Esters from ketones

From amides

Ketone esters

Ketone ketonic ester

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