Azabicyclo octanone

Amides are weak bases with pA values in the range of 0 to —2. When amide resonance is prevented, as in l-azabicyclo[2.2.2]octanone, N-protonation is preferred. ... 

A solution of 50 g of 1 -azabicyclo [2.2.2] -3-octanone hydrochloride in 200 cc of water was hydrogenated at room temperature and 50 atm pressure with 1 g of platinum oxide as catalyst. After the calculated amount of hydrogen had been absorbed, the mixture was filtered and concentrated in vacuo to dryness. The residual product was recrystallized from a mixture of methanol and acetone and formed prisms melting above 300°C. It was identified as 1 -ezabicy-clo[2.2.2] -3-octanol hydrochloride. 

F. Moll, Kondensierte Azehdinone-(2). 4. Mitt. Reactionen von 1-Azabicyclo[4,2,0] octanon-(2) und von 3-Phenyl-l-azabi-cyclo[4,2,0]octanon-(2) , Arch. Pharm. (Wein-heim, Ger.) 1968, 301, 272-281. 

The photochemistry of certain A-substituted heterocycles has also been studied. As part of a continuing investigation of the photolysis of A-nitroso compounds in solution, the conversion of A-nitroso-3-azabicyclo[3.2.2]nonane (65) into the oxime (66) by photolysis in the presence of acid was reported.58 N-Nitrosopyrrolidine is similarly transformed. The mechanism of this reaction is said58 to involve elimination of NOH with the formation of an imine as intermediate, and, in fact, in the photolysis of 2-ethyl-A-nitrosopiperidine (67), the tetrahydropyridine (68) is the major product. This mechanism certainly does not operate in the photolysis of iV-nitroso-2-azacyclo-octanone, which can be rationalized on the basis of an intramolecular hydrogen transfer [Eq. (16)].59 Acyclic iV-nitrosoamides behave in a similar fashion to IV-nitrosoamines.60... 

Becker, D. P., Flynn, D. L. Studies of the solid-phase Pauson-Khand reaction selective in-situ enone reduction to 3-azabicyclo[3.3.0]octanones. Tetrahedron Lett. 1993, 34, 2087-2090. 

Indium trichloride and indium triflate are good catalysts also for the imino Diels-Alder reactions. With 20 mol% InClj, N-benzylideneaniline reacts with cyclopentadiene to give the corresponding tetrahydroquinoline derivative (Scheme 8.104) [134]. Similar InCls-catalyzed imino Diels-Alder reachons proceed with 3,4-dihy-dro-2H-pyrane, indene [135], and cychc enamides [136]. In contrast, cyclohexen-2-one gives no phenanthridinone, but azabicyclo [2.2.2]octanone is isolated (Scheme 8.105) [137]. The reachon seems to proceed through the formahon of die-nolate ion by strong coordinahon of InCb with the enone. 

A solution of 50 g of the above ketone-hydrochloride in 30 cc of water was made alkaline by the addition of 30 g of potassium hydroxide. After the alkali was dissolved, 35 g of granular potassium carbonate were added. The free basic ketone was then extracted from the viscous mixture by shaking with 4 portions of hot benzene (300 cc in each portion). The benzene extracts were decanted, filtered over sodium sulfate in order to remove any suspended alkali, and concentrated in vacuo. The residual 1-azabicyclo[2.2.2]-3-octanone was purified by sublimation (50°-70 C/0.5 mm Hg) it can also be purified by recrystallization from petroleum ether. It formed feathery crystals melting at 147°-148 C. 

Several other groups have reported effective dioxirane systems employing Oxone as the terminal oxidant. For example, Armstrong et al. have developed a spirocyclic iV-carbethoxy-azabicyclo[3.2.1]octanone precatalyst, which affords up to 91.5% ee in the epoxidation of stilbenes (eq 102). Shing et al. have developed an arabinose-derived ketone and employed this in the enantioselective synthesis of the Taxol side chain however, enantioselectivities for the epoxidation were only up to 68% (eq 103). Bortolini et al. have also described the epoxidation of alkenes with the stoichiometric keto bile acid-Oxone system, a range of ee values were observed over several substrate types but up to 98% was observed for the epoxidation of tran -stilbene, although the yield was only 50% (eq 104). ... 

Most recently, oxa-di-Jt-methane rearrangement in aza-bicyclo[2.2.2]oct-2-en-5-one was explored this provides a novel route to pyrrozolidine alkaloids. Thus, sensitized irradiation of 126 and 128 furnished azabicyclo[3.3.0]octanones 127 and 129, respectively (Scheme 24). However, the derivatives 130 did not undergo the oxa-di-Jt-methane reaction. ... 

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