Amines carbonyl compounds

Imines and iminium ions are nitrogen analogs of carbonyl compounds and they undergo nucleophilic additions like those involved in aldol reactions. The reactivity order is C=NR < C=0 < [C=NR2]+ < [C=OH]+. Because iminium ions are more reactive than imines, the reactions are frequently run under mildly acidic conditions. Under some circumstances, the iminium ion can be the reactive species, even though it is a minor constituent in equilibrium with the amine, carbonyl compound, and unprotonated imine. 

Type I MCRs are usually reactions of amines, carbonyl compounds, and weak acids. Since all steps of the reaction are in equilibrium, the products are generally obtained in low purity and low yields. However, if one of the substrates is a bi-funchonal compound the primarily formed products can subsequently be transformed into, for example, heterocycles in an irreversible manner (type II MCRs). Because of this final irreversible step, the equilibrium is forced towards the product side. Such MCRs often give pure products in almost quantitative yields. Similarly, in MCRs employing isocyanides there is also an irreversible step, as the carbon of the isocyanide moiety is formally oxidized to CIV. In the case of type III MCRs, only a few examples are known in preparative organic chemistry, whereas in Nature the majority of biochemical compounds are formed by such transformations [3]. 

Reductions of isolated double bonds in alcohols, amines, carbonyl compounds, acids, etc., are discussed in the appropriate sections. 

Ethers, sulfides, amines, carbonyl compounds, and imines are among the frequently encountered Lewis bases in the ylide formation from such metal carbene complex. The metal carbene in the ylide formation can be divided into stable Fisher carbene complex and unstable reactive metal carbene intermediates. The reaction of the former is thus stoichiometric and the latter is usually a transition metal complex-catalyzed reaction of a-diazocarbonyl compounds. The decomposition of a-diazocarbonyl compounds with catalytic transition metal complex has been the most widely used approach to generate reactive metal carbenes. For compressive reviews, see Refs 1,1a. 

Thus, precursors such as hydrocarbon ethers, amines, carbonyl compounds which are readily protonated tend to be more amenable to ECF than, say, hydrocarbons or halocarbons whose solubilities and conductivities are low. A number of techniques have been developed in the past decade, however, to overcome such problems (see Sect. 4.2). Similarly, advances in methodology of ECF now allow the fluorination of gaseous, liquid, solid, and even polymeric materials [72-77]. 

Keywords primary amine, carbonyl compound, gas-solid reaction, /V-alkyl-azo-methine... 

Capillary electrophoresis has been used for the analysis of chiral pollutants, e.g., pesticides, polynuclear-aromatic hydrocarbons, amines, carbonyl compounds, surfactants, dyes, and other toxic compounds. Moreover, CE has also been utilized to separate the structural isomers of various... 

Among four-component condensations is that of amines, carbonyl compounds, certain acids (HO, HSe-, S2032, N3, NCO, NCS", and RCOO"), and isocyanides, which leads to a-amino acid derivatives ... 

Homoallylic alcohols and amines. Carbonyl compounds and allylic bromides react in the presence of Ph2Cr, which is prepared by adding PhMgBr to a CrCh suspension in THF containing TMEDA. For enones 1,2-addition is observed. The synthesis of homoallylic amines from imines and allylic bromides requires only CrCh and BFj OEt2-... 

In the presence of a base, hydroxylamine-G-sulfonic acid or chloramine aminate carbonyl compounds nucleophilically (Schmitz 1961), e.g. ... 

Different from their previous reports, Hashimoto and co-workers developed a novel reaction in 2009. They found that allylic C—H bond amina-tion reaction occurs when silyl enol ether 120 derived from cyclohexanone is used. This interesting insertion reaction is ascribed to the fact that silyl enol ether 120 can just be -shaped. On the other hand, when Z-shaped silyl enol ethers 118 were employed (Scheme 1.43, top), the aziridination reactions occurred under similar conditions. After treating with trifluoroacetic acid, the a-aminated carbonyl products 119 were obtained in high levels of enan-tioselectivity. Starting from the p-aminated carbonyl compound 121, they accomplished the formal synthesis of (-)-pancracine (Scheme 1.43, bottom). 

CE has been used for the analysis of chiral pollutants, e.g., pesticides, polynuclear aromatic hydrocarbons, amines, carbonyl compounds, surfactants, dyes, and other toxic compounds. Moreover, CE has also been utilized to separate the structural isomers of various toxic pollutants such as phenols, polyaromatic hydrocarbons, and so on. Sarac, Chankvetadze, and Blaschke " resolved the enantiomers of 2-hydrazino-2-methyl-3-(3,4-dihydroxyphenyl)propanoic acid using CD as the BGE additive. The CDs used were native, neutral, and ionic in nature with phosphate buffer as BGE. Welseloh, Wolf, and Konig investigated the CE method for the separation of biphenyls, using a phosphate buffer as BGE with CD as the chiral additive. Miura et al., used CE for the chiral resolution of seven phenoxy acid herbicides using methylated CDs as the BGE additives. Furthermore, the same group resolved 2-(4-chlorophenoxy) propionic acid (MCPP), 2-(2,4-dichlorophenoxy) propionic acid (DCPP), (2,4-dichlorophenoxy) acetic acid (2,4-D), 2-(4-chlorophenoxy) propionic acid (2,4-CPPA), [(2,4,5-... 

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