Amines from amine oxides

Primary amines form Schiff bases, (CH3 )2C=NR. Ammonia induces an aldol condensation followed by 1,4-addition of ammonia to produce diacetone amine (from mesityl oxide), 4-amino-4-methyl-2-pentanone [625-04-7] (CH2)2C(NH2)CH2COCH2, and triacetone amine (from phorone),... 

It explodes on heating (and presumably would be formed if distillation of hydroxyl-amine from calcium oxide were attempted). 

A similar mechanism was invoked by Ohshima and Kawabata (2) to account for their results in the nitrosation of tertiary amines and amine oxides. In applying these concepts to the nitrosative dealkylation of tetraalkyltetrazenes, Michejda al. 5) introduced an interesting variant by suggesting that immonium ions could be formed in two successive one-electron oxidation steps (for example by ferric ion oxidation of tertiary amine to the radical cation followed by radical abstraction of a hydrogen atom from the alpha position), rather than exclusively through the one-step removal of a hydride ion as nitroxyl. The resulting immonium ion was again considered to react directly with nitrite to produce the N-nitroso derivative. These reactions are summarized in Fig. 2b. 

ALKANOLAMNES - AL KAN OL AMINES FROM OLEFIN OXIDES AND AMMONIA] (Vol 2)... 

It is sometimes desirable to have surfactants that can act as biocides as well, especially in cleaning and sanitizing applications. Some cationic surfactants are toxic to bacteria, fungi, and algae. The most common biocidal surfactants have quaternary ammonium polar groups, ranging from quaternary amines to amine oxides. 

In another type of elimination reaction, called Ei or intramolecular, the base, which removes the proton, is another part of the same molecule. Such eliminations from amine oxides or sulfoxides have five-membered-ring transition states. These transition states are more stable with syn than with anti orientations of proton and leaving group, producing very high syn stereoselectivity. 

Dioxiranes, prepared from acetone and other aliphatic ketones by treatment with Oxone, can accomplish oxidations that are usually not achieved by Oxone itself [210, 211], Dioxiranes can be isolated by vacuum codistillation with the respective ketones [210], or else, they may be formed in situ and applied in the same reaction vessel [210, 211]. Examples of the applications of dioxiranes are epoxidations 210] and the oxidation of primary amines to nitro compounds [211], of tertiary amines to amine oxides [210], and of sulfides to sulfoxides [210] (equation 12). 

Oxidations with m-chloroperoxybenzoic acid are carried out in solutions in hexane, dichloromethane, chloroform, methanol, or tetrahydro-furan at temperatures ranging from -78 to 40 C. The applications of m-chloroperoxybenzoic acid are epoxidation [287, 314, 315, 316] the Baeyer-Villiger reaction [286, 315, 317, 378] and the oxidation of primary amines to nitro compounds [379], of tertiary amines to amine oxides [320], of sulfides to sulfoxides [327, 322, 323, 324], and of selenides to selenones [325]. Secondary alcohols are oxidized to ketones in the presence of hydrogen chloride [326], and acetals are oxidized to esters with boron trifluoride etherate as a catalyst [327]. The addition of potassium fluoride to reaction mixtures facilitates product isolation, because both m-chloroben-zoic acid and the unreacted m-chloroperoxybenzoic acid are precipitated... 

Table 1 Endo- vj. Exo-cyclic Elimination from Amine Oxide Pyrolysis...

Chiao, W.-B., Saunders, W. H., Jr. Mechanisms of elimination reactions. 29. Deuterium kinetic isotope effects in eliminations from amine oxides. The consequences of nonlinear proton transfer. J. Am. Chem. Soc. 1978,100, 2802-2805. 

Octyl alcohol, 34, 3 -Octyl fluoride, 36, 42 1-Octyl nitrite, 38, 75 Olefins from amine oxides, 39, 41, 42 Oleic acid, 37, 66, 68, 77 39, 15 Oleoyl chloride, 37, 66 Orthocarbonic acid, tetraethyl ESTER, 32, 68... 

For more complex examples, Cerero and co-workers used the Cope elimination to prepare enone 17, a key intermediate in Paquette s approach to the taxanes, from amine oxide 16.9... 

Deoxygenation. Removal of the oxygen atom from amine oxides with the mixed anhydride at the temperature of ice is quite convenient. The mixed anhydride is formed and used in situ from HCOONa and pivaloyl chloride. 

Commercial acrolein contains an inhibitor such as hydroquinone samples from which the inhibitor has been removed (e.g., by distillation) are extremely hazardous. Because of its corrosivity, flammability, and high acute toxicity, acrolein should be handled using the "basic prudent practices" of (Chapter 5.C, supplemented by the additional precautions for work with compounds of high toxicity (Chapter 5.D) and extremely flammable substances (Chapter 5.F). In particular, work with acrolein should be conducted in a fume hood to prevent exposure by inhalation, and splash goggles and butyl rubber gloves should be worn at all times to prevent eye and skin contact. Acrolein should be used only in areas free of ignition sources. Containers of acrolein should be stored in secondary containers in areas separate from amines, oxidizers, acids, and bases. 

Samarium diiodideIhexamethylphosphoramide Cyclic tert. amines from N-oxides s. 44, 993... 

Thioethers. A mixture of diphenyl sulfoxide and HMPA treated with SmL in THF under N2 at 20 for 1 min, diluted with hexane, and filtered through Florisil - diphenyl sulfide. Y 94%. The method can also be used for the rapid deoxygenation of sulfones (which may be viewed as protected thioethers). E Diphenyl sulfone under the same conditions - diphenyl sulfide. Y 93%. Esters remained intact and, in some cases, sulfoxides were selectively reduced in the presence of ketones. F.e. inch formation of cyclic tert. amines from N-oxides, tert. phosphines from phosphine oxides, and distannanes from distannoxanes, s. Y. Handa et al., J. Chem. Soc. Chem. Commun. 1989, 298-9 review of synthesis and use of polysulfoxides s. V.A. Nikonov, G.V. Leplyanin, Sulfur Reports 9, 1-23 (1989). 

Sodium sulfide/irradiation Amines from N-oxide radicals... 

Tertiary amines have also been prepared from amine oxides/ quaternary 1,1-silylammonium ylides/ olefins/ and a-aminothioethers. ... 

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