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Synthesis aldehydes from carboxylic

The synthesis of aldehydes from carboxylic acids. Mosettig, E., Org. Reactions 8, 218 (1954). [Pg.257]

E. Mosettig, The Synthesis of Aldehydes from Carboxylic Acids, Org. React. 1954, 8, 218-257. [Pg.320]

The Synthesis of Aldehydes from Carboxylic Acids Erich Mosettig... [Pg.419]

Aldehydes from carboxylic acids. Japanese chemists have reported the synthesis of aldehydes or aldehydic acids from carboxylic anhydrides using this reagent. Yields are in the range of 30-90%. [Pg.550]

Aldehydes from carboxylic and chlorides yia a-diazoketones and 1-acylpyrazoles Synthesis with addition of 1 C-atom... [Pg.385]

Notable examples of general synthetic procedures in Volume 47 include the synthesis of aromatic aldehydes (from dichloro-methyl methyl ether), aliphatic aldehydes (from alkyl halides and trimethylamine oxide and by oxidation of alcohols using dimethyl sulfoxide, dicyclohexylcarbodiimide, and pyridinum trifluoro-acetate the latter method is particularly useful since the conditions are so mild), carbethoxycycloalkanones (from sodium hydride, diethyl carbonate, and the cycloalkanone), m-dialkylbenzenes (from the />-isomer by isomerization with hydrogen fluoride and boron trifluoride), and the deamination of amines (by conversion to the nitrosoamide and thermolysis to the ester). Other general methods are represented by the synthesis of 1 J-difluoroolefins (from sodium chlorodifluoroacetate, triphenyl phosphine, and an aldehyde or ketone), the nitration of aromatic rings (with ni-tronium tetrafluoroborate), the reductive methylation of aromatic nitro compounds (with formaldehyde and hydrogen), the synthesis of dialkyl ketones (from carboxylic acids and iron powder), and the preparation of 1-substituted cyclopropanols (from the condensation of a 1,3-dichloro-2-propanol derivative and ethyl-... [Pg.144]

Of the four components reacting in the Ugi reaction, the isocyanide and the carboxylic acid have only limited influence on the overall stereoselection. For instance, in the synthesis of 13-demethyldysidenin (R)-l and 13-demethylisodysidenin (S)-l from a chiral aldehyde, chiral carboxylic acid, isonitrile and methylamine79. [Pg.799]

For example, use of 10 different isocyanides and amines, along with 40 different aldehydes and carboxylic acids has the potential to generate 160,000 different dipeptide analogs.65 This system was explored by synthesizing arbitrarily chosen sets of 20 compounds that were synthesized in parallel. The biological assay data from these 20 combinations were then used to select the next 20 combinations for synthesis. The synthesis-assay-selection process was repeated 20 times. At the end of this process the average inhibitory concentration of the set of 20 products had been decreased from 1 mM to less than 11xM. [Pg.1256]

A common procedure in C-C-bond formation is the aldol addition of enolates derived from carboxylic acid derivatives with aldehydes to provide the anion of the [5-hydroxy carboxylic acid derivative. If one starts with an activated acid derivative, the formation of a [Mac lone can follow. This procedure has been used by the group of Taylor [137] for the first synthesis of the l-oxo-2-oxa-5-azaspiro[3.4]octane framework. Schick and coworkers have utilized the method for their assembly of key intermediates for the preparation of enzyme inhibitors of the tetrahydrolipstatin and tetrahydroesterastin type [138]. Romo and coworkers used a Mukaiyama aldol/lac-tonization sequence as a concise and direct route to 3-lactones of type 2-253, starting from different aldehydes 2-251 and readily available thiopyridylsilylketenes 2-252 (Scheme 2.60) [139]. [Pg.86]

The formation of 1,2,3-trioxolanes from an alkene and ozone is the first step in the ozonolysis reaction, which is widely used in synthesis to convert alkenes to aldehydes or carboxylic acids. No instances of double bond migration during ozonolysis are known (since the first step is a cyclo-... [Pg.579]

Structure of the Carbonyl Group 817 18-3 Nomenclature of Ketones and Aldehydes 818 18-4 Physical Properties of Ketones and Aldehydes 820 18-5 Spectroscopy of Ketones and Aldehydes 822 18-6 Industrial Importance of Ketones and Aldehydes 828 18-7 Review of Syntheses of Ketones and Aldehydes 829 18-8 Synthesis of Ketones from Carboxylic Acids 833 18-9 Synthesis of Ketones and Aldehydes from Nitriles 833... [Pg.17]

Commercial RuC13 xH20 is widely used as a catalyst (see references 3 and 2320 for details of earlier studies). Examples include the oxidation of amines and alcohols,2321 the production of glycol esters from synthesis gas,2322 and the generation of 1,3-diol derivatives from reaction of dienes and alkenes with aldehydes and carboxylic adds.2323... [Pg.444]

Ozone, while somewhat inconvenient to use, is way qiecific in its reactions with alkenes. It is widely employed for selective synthesis, for qualitative and quantitative analysis of unsaturated compounds, and for studying the position of double bonds in macromolecules. The nature of the products obtained from ozonolysis reactions is determitted by the way in which the reaction is carried out Different workup procedures (hydrolytic, reductive or oxidative) can be used to produce alcohols, aldehydes, ketones, carboxylic acids or esters. [Pg.542]

As an example of scaffold synthesis rather than decoration, we adapted the Lacey-Dieckmann synthesis of tetramic acids to a combinatorial strategy (Figure 6). The overall sequence is only three steps, and all the three reaction inputs involve readily available building blocks amino acids, aldehydes, and carboxylic acids. We published both solution- and solid-phase protocols, and this was followed soon thereafter by similar reports from industrial groups. Clearly, the ability to access this heterocycle with ample room for diversification was highly attractive, and each of us had independently developed this idea. [Pg.99]

Acylsilanes are versatile intermediates for carbon-carbon bond formation reactions, and may serve as precursors for the synthesis of silyl enol ethers, aldehydes, or carboxylic acids. In the presence of a base or certain nucleophiles, they undergo the Brook rearrangement, where the silyl moiety migrates from carbon to oxygen (see below in this section). [Pg.320]

In analogy to the synthesis of iminium salts (Section 4.2.2.1.), acyiiminium ions (60) can be obtained from carbonyl precursors (1), such as ketones or aldehydes, and carboxylic acid amides (62 Scheme 30). In addition, other amides can be used, such as p-toluenesulfonamides, which lead to the corresponding N-tosylated iminium salts. ... [Pg.744]

Dondoni, A., Daninos, S., Marra, A., and Formaglio, P, Synthesis of ketosyl and ulosonyl phosphonates by Arbuzov-type glycosidation of thiazolylketol acetates. Tetrahedron, 54, 9859, 1998. Razumov, A.L, and Moskva, V.V., Derivatives of phosphonic and phosphinic acids. Part 26. Synthesis of phosphorylated carboxylic acids from aldehydes and acetals, Zh. Obshch. Khim., 35, 1149, 1965 J. Gen. Chem. USSR (Engl. Transl.), 35, 1151, 1965. [Pg.256]


See other pages where Synthesis aldehydes from carboxylic is mentioned: [Pg.623]    [Pg.285]    [Pg.356]    [Pg.174]    [Pg.130]    [Pg.95]    [Pg.125]    [Pg.821]    [Pg.258]    [Pg.406]    [Pg.199]    [Pg.282]    [Pg.55]    [Pg.174]    [Pg.66]    [Pg.258]    [Pg.1119]    [Pg.426]    [Pg.478]    [Pg.980]   


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Aldehydes synthesis from

Carboxylate, synthesis

Carboxylic synthesis

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