Amine oxides phthalimides

Because the reactions of related in -cyclohexadienyl complexes are synthetically valuable, the reactions of this ligand have been studied extensively. An outline of how this chemistry can be conducted on the Fe(CO)j fragment is shown in Equation 11.51. A variety of cyclohexadienes are readily available from Birch reduction of substituted aromatics. Coordination and abstraction of a hydride, typically by trityl cation, leads to cationic cyclohexadienyl complexes. These cyclohexadienyl complexes are reactive toward organolithium, -copper, -cadmium, and -zinc reagents, ketone enolates, nitroal-kyl anions, amines, phthalimide, and even nucleophilic aromatic compounds such as indole and trimethoxybenzene. Attack occurs exclusively from the face opposite the metal, and exclusively at a terminal position of the dienyl system. This combination of hydride abstraction and nucleophilic addition has been repeated to generate cyclohexa-diene complexes containing two cis vicinal substituents. The free cyclohexadiene is ttien released from the metal by oxidation with amine oxides. ... 

Phosphine(s), chirality of, 314 Phosphite, DNA synthesis and, 1115 oxidation of, 1116 Phospholipid, 1066-1067 classification of, 1066 Phosphopantetheine, coenzyme A from. 817 structure of, 1127 Phosphoramidite, DNA synthesis and, 1115 Phosphoranc, 720 Phosphoric acid, pKa of, 51 Phosphoric acid anhydride, 1127 Phosphorus, hybridization of, 20 Phosphorus oxychloride, alcohol dehydration with. 620-622 Phosphorus tribromide, reaction with alcohols. 344. 618 Photochemical reaction, 1181 Photolithography, 505-506 resists for, 505-506 Photon, 419 energy- of. 420 Photosynthesis, 973-974 Phthalic acid, structure of, 753 Phthalimide, Gabriel amine synthesis and, 929... 

Known examples of N—H oxidative addition prior to 1980 usually involved the addition of relatively acidic N—H bonds, for example that in phthalimide, to Pd(0) or Pt(0) centres. Work by Milstein in the 1980s showed that the parent amine NH3 can oxidatively add to Ir(I) centres (see Section 6.2.4) under mild conditions to afford parent amido hydrides in good... 

The reaction with ammonia or amines, which undoubtedly proceeds by the SNAr mechanism, is catalyzed by copper8" and nickel105 salts, though these are normally used only with rather unreactive halides.106 This reaction, with phase transfer catalysis, has been used to synthesize triarylamines.107 Copper ion catalysts (especially cuprous oxide or iodide) also permit the Gabriel synthesis (0-58) to be applied to aromatic substrates. Aryl bromides or iodides are refluxed with potassium phthalimide and Cu 0 or Cul in dimethylacetamide to give N-aryl phthalimides, which can be hydrolyzed to primary aryl amines.108... 

Intramolecular PET cyclizations of aminoalkyl-substituted phthalimides were investigated by the groups of Kanaoka and Coyle [168-171]. Because of the relatively low oxidation potentials of tertiary amines, these electron-transfer reactions are highly exergonic [172, 173]. The regioselectivity of the CH-activation step was remarkably high for the A -methyl, A -phenyl substituted substrates (Scheme 43). 

The synthesis of N phthaloyl enamides has been reported by a remarkably general method for aerobic oxidative amination of unactivated alkyl olefins as shown in Scheme 9.6 [12]. From a practical synthesis point of view, the phthalimide can not only serve as a directing group for asymmetric hydrogenation but can also be removed under mild conditions. 

The phthalimide functional group has absorption and ET properties which make it very attractive in terms of PET processes in which it is the oxidizing species. The application of phthalimide derivatives in carbon-carbon bond forming processes with electron-donating groups such as ethers, thioethers, amines, arenes, carboxylates, etc., has been reviewed. A PET decarboxylation-cycliz-ation sequence has been used for the synthesis of medium-sized (8-16) heterocyclic ring systems (15) from AT-phthaloylanthranilic amides coupled to ca-aminoacids (14). The same PET protocol has been used to convert di-, tri-, and tetrapeptides into cyclopeptides with a minimum of protection and activation... 

Our return to amination chemistry was inspired by the mechanistic studies of the Ullman reaction (Scheme 8). Hartwig had shown that the Cu(I)-phthalimide complex (38) could undergo oxidative addition with aryl halides to form a Cu(lll) intermediate (39), which then reductively eliminated to form a C—N bond (40). We hypothesized that a Cu(III)-phthalimide intermediate (42) could also be created by oxidation of 38 and a subsequent C—H metalation, presumably via a CMD mechanism (Scheme 8). Consequently, we synthesized 38 and reacted it with a series of oxidants and arenes in an attempt to discover a synthesis of protected anilines (e.g., 40) via C-H activation. The initial reactions were performed using stoichiometric amoimts of 38, but we intended to lower the catalyst loading once a lead reaction was discovered. 

In keeping with the seminal work of Kita, we proposed that the I(III)-mediated amination involved a radical cation intermediate that was generated by single electron transfer from the arene to the I(III) oxidant. The consequent radical cation should be highly reactive, and the attack of a phthalimide nucleophile would lead to a mixture of regiomeric products, like the 5 6 3 mixture that was observed for our toluene reaction (Scheme 10). This hypothesis contrasts with the mechanisms proposed by Chang and Antonchick, as electrophilic aromatic substitution, even with a reactive R2N species, should favor the para product. 

Of the hundreds of chemicals that are efiective as antimicrobials, only a few are used in plastics applications. The most common group of active ingredients consists of 10,16-oxybisphenoxy arsine (OBPA, tradenames Intercide, Akzo Chemical Vinyzene, Morton International), 2- -octyl-4-isothia-zolin-3-one (tradenames Micro-Check 11, Ferro Corporation Vinyzene IT, Morton International), N-trichloro-methylthio-4-cycIohexene-l,2-dicarboximide (Captan, tradenames Vancide 89, R.T. Vanderbilt Fungitrol C, Hiils America), and N-(trichloromethylthio) phthalimide (Flopet, trade name Fungitrol 11, Huls America). Other antimicrobial active ingredients include amine-neutralized phosphate and zinc 2-pyridinethiol-l-oxide. 

Stahl has also shown that the product from oxidative amination of simple alkenes forms in the presence of a Pd(II) complex and dioxygen without copper. The analogous reactions conducted in the presence of copper led to isomerization of the olefin by an unknown mechanism, and a mixture of products was formed. Thus, the reactions conducted with Oj as oxidant in the absence of copper are more selective. An example of the reaction with phthalimide as nitrogen donor in the absence of copper is shown in Equation 16.119. 

The direct electrosynthesis of S—N bonds from disulfides and amines has been shown to occur through a reaction of the amine with the oxidized disulfide being a strong electrophile. In contrast to the results, the cross-coupling of phthalimide (16) with disulfide does not proceed in a direct electrolysis. However, the electrosynthesis of sulfenimides (17) can be achieved by a [Br] -mediated cross-coupling reaction of imides with disulfides (Scheme 7). The electrolysis of a mixture of (16) and dicyclohexyl disulfide in an MeCN-NaBr-(Pt) system affords... 

Electrochemical oxidation and reduction of het-ero atom compounds, such as N, S, and P compounds, has been intensively studied and utilized for synthesis of many fine chemicals [1-4]. Electrooxidative S-S, S-N, S-P, and N-P bond formation is performed successfully by electrolysis of thiols, disulfide/amine, disulfide/phosphate, amine/ phosphate, and so on, affording useful chemicals, e.g., thiuram disulfide [17], sulfenamide [18], sulfenimides [19], phosphorothiolates [20], phosphoramidate [21], and so on. For instance, cross-coupling of phthalimide and dicyclohexy disulfide is performed by electrolysis in acetonitrile containing a catalytic amount of sodium bromide under a ccaistant apphed voltage (3 V, 0.7-0.9 V vs. SCE) to afford N-(cyclohexylthio)phthalimide, an important prevulcanization inhibitor in the rubber industry, in quantitative yield [19] (Fig. 4). 

Metal ions or metals in zero oxidation state are used as templates. Template syntheses based on phthalimide and phthalic anhydride require an aminating agent (for instance, urea) and catalysts (ammonium molybdate, boric acid, ZrCl4) [455-457]. In all cases the reaction proceeds either in a molten mixture of the reagents or in an inert high-boiling solvent (nitrobenzene, chloronaphthalene, o-dichlorobenzene, trichlorobenzene, ethylene glycol) [456-460]. 

There are several acid precursors that use an oxidation reaction to "unmask an acid surrogate to give a carboxylic acid. Several of these approaches are outlined in this section. Oxidation of a primary alcohol to a carboxylic acid using chromium (VI) reagents is perhaps the most common approach and is illustrated by oxidation of the primary alcohol moiety in phthalimidoyl alcohol 1.199 (prepared by literature methods). Subsequent catalytic hydrogenation of the triple bond gave 4-(phthal-imido)but-2Z-enoic acid, 1.200. Treatment with diethylamine converted the phthalimide group to an amine moiety in 4-aminobut-2Z-enoic acid, 1.201. 

Stoichiometric intermolecular amination reactions of arenes have been explored to a larger extent recently. Of major interest had been the investigation on the behavior of phthalimide in the presence of hypervalent iodine as oxidation promoter, which was simultaneously reported by DeBoef and Chang (Scheme 6) [20, 21], The respective reactions of p-xylene 26 to 2-phthaloyl xylene 27 and arenes 28 to... 

With this polymerization scheme, end-groups can be readily converted to thermo-oxidatively stable imide moieties anhydrides, by treatment with aniline, and amines, by treatment with phthalic anhydride, give N-phenyl ether-imide and N-aryl phthalimide end-groups, respectively. The presence of small amounts of moisture is of no consequence in these polymerizations since it is simply evolved along with the rest that is formed during the imidization. 

Weine, B., Baeza, A., Jerphagnon, T., et al. (2009). Aldehyde Selective Wacker Oxidations of Phthalimide Protected AUyUc Amines aNew Catalytic Route to j83-Amino Acids, / Am. Chem. 

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