Olefins from amine oxides

Cope, A. C., Ciganek, E., Howell, C. F., Schweizer, E. E. Amine oxides. VIII. Medium-sized cyclic olefins from amine oxides and quaternary ammonium hydroxides. J. Am. Chem. Soc. 1960, 82,4663-4669. 

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... 

A. C. Cope and E. R. Trumbull, "Olefins from Amines. The Flofmann Elimination Reaction and Amine Oxide Pyrolysis," Organic Reactions 11, 317 (1960). 

Cope, A. C., Trumbull, E. R. Olefins from amines the Hofmann elimination reaction and amine oxide pyrolysis. Org. React. 1960,11, 317-493. 

Olefins from Amines The Hofmann Elimination Reaction and Amine Oxide... 

The orientational behaviour of amine oxide pyrolyses has been adequately summarised by Cope and TrumbulE . As for the acetate decompositions, orientation in the simple alkyl systems is controlled primarily by statistical factors but departure from this influence is noted with the bulky r-butyl substituent and the acid strengthening beta phenyl substituents Eclipsing effects are greater in the planar five-membered transition states than in the puckered six systems and this is borne out by the greater preference for trans-olefin formation from amine oxides than esters and xanthates (152, cf. 149). 

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

Cope, A.C., Trumbull, E.R. (1975) Olefins from Amines The Hofmann Elimination Reaction and Amine Oxide Pyrolysis in Organic Reactions, RE Krieger Publ. Co., New York. 

The mechanism is supported by findings from the decomposition reaction of the amine oxides derived from threo- and cryt/zro-2-amino-3-phenylbutane. The t/zrco-amine oxide 6 yields -2-phenylbut-2-ene 7 with a selectivity of 400 1, and the cryt/zro-derivative 8 yields the Z-olefin 9 with a selectivity of 20 1 ... 

The primary products obtained from 2-butanol are of mechanistic. significance and may be compared with other eliminations in the sec-butyl system 87). The direction of elimination does not follow the Hofmann rule 88) nor is it governed by statistical factors. The latter would predict 60% 1-butene and 40% 2-butene. The greater amount of 2-alkene and especially the unusual predominance of the cis-olefin over the trans isomer rules out a concerted cis elimination, in which steric factors invariably hinder the formation of cis-olefin. For example, the following ratios oicisjtrans 2-butene are obtained on pyrolysis of 2-butyl compounds acetate, 0.53 89, 90) xanthate, 0.45 (S7) and amine oxide, 0.57 86) whereas dehydration of 2-butanol over the alkali-free alumina (P) gave a cisjtrans ratio of 4.3 (Fig. 3). 

The present preparation of methylenecyclohexane is an example of an amine oxide pyrolysis. This route from amines to olefins in many cases yields pure olefins where the alternative method, the Hofmann exhaustive methylation reaction, is accompanied by some rearrangement to more stable isomeric olefins. 

Miscellaneous. Aside from the oxidation chemistry described, only a few catalytic applications are reported, including hydrogenation of olefins (114,115), a, [3-unsaturated carbonyl compounds (116), and carbon monoxide (117) and the water gas shift reaction (118). This is so owing to the kinetic inertness of osmium complexes. A 1% by weight osmium tetroxide solution is used as a biological stain, particulady for preparation of samples for electron microscopy. In the presence of pyridine or other heterocyclic amines it is used as a selective reagent for single-stranded or open-form B-DNA (119) (see Nucleic acids). Osmium tetroxide has also been used as an indicator for unsaturated fats in animal tissue. Osmium tetroxide has seen limited if controversial use in the treatment of arthritis (120,121). 

Antistatic agents - [ALKANOLAMINES - ALKANOLAMINES FROM OLEFIN OXIDES AND AMMONIA] (Vol 2) - [ALKANOLAMINES - ALKANOLAMINES FROM OLEFIN OXIDES AND AMMONIA] (Vol 2) - [AMINE OXIDES] (Vol 2) - [ANTISTATIC AGENTS] (Vol 3) - [AMINES-FATTY AMINES] (Vol 2) - [PHOSPHORUSCOMPOUNDS](Voll8) -castor oil derivatives as [CASTOR OIL] (Vol 5) -from polyammes pIAMINES AND HIGHER AMINES ALIPHATIC] (Vol 8) -in styrene plastics [STYRENE PLASTICS] (Vol 22) -for textiles [SUGAR ALCOHOLS] (Vol 23)... 

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 1,1-difluoro olefins (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 l,3-dichloro-2-propanol derivative and ethyl-... 

The amine-oxide (316) reacts with trifluoroacetic anhydride in the manner depicted in Scheme 13. The iminium ion (317) has the properties of a Mannich reagent, and alkylates a second steroid molecule in the enamine form (318) to give the 2-methylene-3-ketone (31-9) after hydrolysis. The demethylated amine was formed at the same time. Different behaviour of the A -unsaturated amine oxide (320) results from participation of the olefinic bond in a novel type of Grob... 

J.K. Cha et al. developed a stereocontrolled synthesis of bicyclo[5.3.0]decan-3-ones from readily available acyclic substrates. Acyclic olefin-tethered amides were first subjected to the intramolecular Kulinkovich reaction to prepare bicyclic aminocyclopropanes. This was followed by a tandem ring-expansion-cyclization sequence triggered by aerobic oxidation. The reactive intermediates in this tandem process were aminium radicals (radical cations). The p-anisidine group was chosen to lower the amine oxidation potential. This substituent was crucial for the generation of the aminium radical (if Ar = phenyl, the ring aerobic oxidation is not feasible). 

Standard Oil Co. (1975) Oil-Soluble Lubricant Bi-Functional Additives from Mannich Condensation Products of Oxidized Olefin Copolymers, Amines and Aldehydes , US Patent 3,872,019. 

As the name suggests, the reverse Cope elimination reaction involves formation of a tertiary amine oxide from a hydroxylamine and olefin.17,18 For example, reaction of N-methylhydroxylamine (49) with 2,2-diphenyl-4-pentenal (50) in ethanol at room temperature gave amine oxide 51 in 51% yield, together with the expected nitrone 52. It has been suggested the mechanism of the reverse Cope reaction could be a radical chain reaction19,20 however, more recent studies have confirmed the mechanism is analogous to the concerted Cope elimination.17... 

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