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Alcohol amine alcohols, synthesis

Sulfonates react with a variety of nucleophiles. Synthesis of M A -bis(trifluoro-methyl)aminotnfluoromethanesulfonate and its reactions with nucleophiles were investigated [33] (equation 31) (Table 13). Nucleophilic attack occurs at either nitrogen or sulfur amines give complex mixtures [33]. Polyfluoroalkyl fluorosul-fates react with amines, alcohols, or alkoxides to yield polyfluoroalkyl sulfamates and dialkyl sulfates, respectively [34] (equation 32) (Table 13). In these reactions. [Pg.577]

Nickel oxide anodes are another example for a relatively simple oxide electrocatalyst used rather widely in the oxidation of organic substances (alcohols, amines, etc.) in alkaline solutions at relatively low anodic potentials (about +0.6 V RHE). These processes, which occur at an oxidized nickel surface, are rather highly selective. As an example, we mention the industrial oxidation of diacetone-L-sorbose to the corresponding acid in vitamin C synthesis. This reaction occurs at nickel oxide electrodes with chemical yields close to 100%. [Pg.544]

Scheme 1. Iron-substituted Silanimines. Synthesis and Reactions with Alcohols, Amins and Acetone. Scheme 1. Iron-substituted Silanimines. Synthesis and Reactions with Alcohols, Amins and Acetone.
SCHEME 35- Synthesis of / -D-galactopyranoside precursors, bearing amine, alcohol, and iodide as anchoring functionalities, for metal-based self-assembly.275... [Pg.272]

Many new sugar based products present the advantage of being non-toxic and biodegradable. The products resulting from the telomerization of 1 with appropriate nucleophiles such as alcohols, amines, water, or carbon dioxide serve generally as useful intermediates in the synthesis of various natural products and fine chemicals [60-63], as precursors for plasticizer alcohols [56, 64], components of diesel fuels [65], surfactants [11, 66], corrosions inhibitors, and non-volatile herbicides [67]. [Pg.114]

The original synthesis of duloxetine (3) is relatively straightforward, involving a four-step sequence from readily available 2-acetylthiophene 30 (Scheme 14.7). Understandably, the main synthetic challenge stems from the presence of a chiral center, because duloxetine (3) is marketed as the (5)-enantiomer as shown. Thus, a Mannich reaction between 30 and dimethylamine generated ketone amine 31, which was then reduced to provide intermediate racemic alcohol amine 32. The desired optically active (5)-alcohol 32a was accessed via resolution of racemate 32 with (5)-(+)-mandelic acid, which provided the necessary substrate for etherihcation with 1-fluoronaphthalene to afford optically active amine 33. Finally, A -demethylation with 2,2,2-trichloroethyl chloroformate and cleavage of the intermediate carbamate with zinc powder and formic acid led to the desired target duloxetine (3). [Pg.207]

For the most part, the preparation of monomeric and polymeric carbamates (urethanes), semicarbazides, and ureas consists of condensation reactions of isocyanates with alcohols, hydrazines, or amines. The synthesis of ureas and semicarbazides are described in Chapters 6 and 8, respectively. [Pg.120]

When the Pd bears chiral ligands, these reactions can be enantioselective.1448 ir-Allylmo-lybdenum compounds behave similarly.1449 Because palladium compounds are expensive, a catalytic synthesis, which uses much smaller amounts of the complex, was developed. That is, a substrate such as an allylic acetate, alcohol, amine, or nitro compound1450 is treated with the nucleophile, and a catalytic amount of a palladium salt is added. The rr-allylpal-ladium complex is generated in situ. Alkene-palladium complexes (introducing the nucleophile at a vinylic rather than an allylic carbon) can also be used.1451... [Pg.468]

Many other uses of a-sulfinyl carbanions are found in the literature, and in the recent past the trend has been to take advantage of the chirality of the sulfoxide group in asymmetric synthesis. Various ways of preparation of enantiopure sulfoxides have been devised (see Section 2.6.2) the carbanions derived from these compounds were added to carbonyl compounds, nitriles, imines or Michael acceptors to yield, ultimately, with high e.e. values, optically active alcohols, amines, ethers, epoxides, lactones, after elimination at an appropriate stage of the sulfoxide group. Such an elimination could be achieved by pyrolysis, Raney nickel or nickel boride desulfurization, reduction, or displacement of the C-S bond, as in the lactone synthesis reported by Casey [388]. [Pg.176]

In contrast to cobalt, rhodium permits a one-step oxo alcohol synthesis in the presence of certain monomeric and polymeric amines (8, 9, 10). Included in this group are triethylamine, N-alkylpiperidines, N-methylpyrrolidine, and N,N-dimethylbenzylamine (DMBA). Initial kinetic data on this amine-promoted alcohol synthesis (under severe reaction conditions) have been reported by B. Fell and coworkers (II), but no attempt has been made to characterize the catalytic species in the reaction cycle. [Pg.250]

One transformation that is closely related to the synthesis of carbamate esters from alcohols, amines and C02, is the formation of cyclic urethanes, such as oxazolidin-2-ones, by reaction of C02 with 1,2-amino alcohols or their formally dehydrated derivatives, aziridines. [Pg.135]

Reactions have been described for RH = amines, alcohols, aromatics, aliphatics, perfluoroalkyls, hydrogen halides, and thiols (167). Another recent use of S2OfiF2 in organic chemistry has been in the synthesis of lactones by the remote oxidation of carboxylic acids using a... [Pg.170]

Like alcohols, amines can form hydrogen bonds and tend to be more soluble in water than many other functional classes. The hydrogen bonds formed by amines in nucleic acids play a critical role in the genetic code. The hydrogen bonds allow the genetic bases to recognize each other, and this controls DNA synthesis and transcription, as well as protein synthesis. [Pg.296]

Linkers are usually categorized according to the kind of functional group or substrate class they can selectively immobilize (linkers for carboxylic acids, alcohols, amines, etc.). Because a variety of types of linker is available for solid-phase synthesis, many belong to certain well-established classes of protecting group (Table 6.1.1) and can therefore be grouped into linker families. The members of each family have certain reactivity patterns in common. [Pg.452]

The preparation and structures of siloxanediol derivatives has been reviewed29,184 but some representative examples of reactions are given below. Two general methods have been used to make metal siloxides from silanols one involves the direct reaction of a silanol with the metal derivative, usually an amide, alkoxide, halide or alkyl (to give amine, alcohol, HX or alkane byproducts respectively), while the second involves the preparation of a simple alkali metal derivative which can then be used as a siloxide transfer reagent for further synthesis. Only the direct route will be considered here. Two of the most useful siloxide transfer species, (MOPh2Si)20 (M = Li or Na), are... [Pg.717]

The last step of the synthesis is a reductive amination of a ketone that is formed by oxidation of the corresponding alcohol. The alcohol results from the Grignard reaction between cyclopentylmagnesium bromide and propylene oxide. [Pg.673]

Reactions using CO in the presence of water (a synthesis gas equivalent via water-gas shift), alcohols, amines, and so on, are generally called carbonylations. Various syntheses are summarized in Fig. 22-8. [Pg.1258]

When intermediate 81 is formed from indole 80 and l,l -carbonyldiimidazole (GDI) using DMAP to promote indole nitrogen acylation in acetonitrile at reflux, it is reasonably stable, observed by TLC, but not isolated. Treatment of intermediate 81 in situ with amines, alcohols, or thiols afforded the desired derivatives 82. During the reaction of indoles with GDI, some carbonyl diindole 83 was formed. In many cases this material could be isolated and characterized. In an alternative approach, alcohols reacted with GDI stoichiometrically to form an unstable intermediate carbamate species 84, which could in turn be reacted with indoles to form the desired indole-1-carboxylates 82. This new methodology for the formation of compound 82 proved to be useful in one of the approaches for the synthesis of novel Serotonergics. [Pg.58]


See other pages where Alcohol amine alcohols, synthesis is mentioned: [Pg.107]    [Pg.14]    [Pg.533]    [Pg.304]    [Pg.189]    [Pg.132]    [Pg.75]    [Pg.71]    [Pg.112]    [Pg.20]    [Pg.155]    [Pg.179]    [Pg.415]    [Pg.519]    [Pg.153]    [Pg.616]    [Pg.66]    [Pg.1332]    [Pg.322]    [Pg.210]    [Pg.1396]    [Pg.84]    [Pg.291]    [Pg.200]    [Pg.195]    [Pg.533]    [Pg.170]   
See also in sourсe #XX -- [ Pg.216 ]




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