26051-25-2Relevant academic research and scientific papers
The Reactivity of 1-Chloro-3,3-dimethylbicyclooctan-2-one in the Radical Mechanism of Nucleophilic Substitution
Santiago, Ana N.,Takeuchi, Ken'ichi,Ohga, Yasushi,Nishida, Mitsuo,Rossi, Roberto A.
, p. 1581 - 1584 (2007/10/02)
1-Chloro-3,3-dimethylbicyclooctan-2-one (5) does not react with diphenyl phosphide ions (4) in liquid ammonia in the dark in 240 min, but under irradiation (30 min) it gives good yields of the substitution product (10) isolated as the oxide 12 (69percent yield) and 3percent yield of the reduction product 3,3-dimethylbicyclooctan-2-one (11).The photostimulated reaction is inhibited by p-dinitrobenzene and 2,2,6,6-tetramethyl-1-piperidinyloxyl.In competition experiments 5 is more reactive (>/= 700) than 1-chloroadamantane (3a) and only slightly less reactive than 1-bromoadama ntane (3b) (0.40) toward diphenyl phosphide ions.On the other hand, 1-chloro-3,3-dimethylbicyclooctane (6) was completely unreactive towards 4 under irradiation.We suggest that the bridgehead chloride 5 reacts by the SRN1 mechanism of nucleophilic substitution and that the 2-oxo substitution increases the reactivity of the chloride due to the LUMO of the carbonyl group.
(13)C magnetic resonance studies. 124. Preparative ring expansions of bicyclic ketones by homoketonization of cylopropoxide analogs
Patel, Vijay,Ragauskas, Arthur J.,Stothers, J. B.
, p. 1440 - 1449 (2007/10/02)
Homoketonization of some readily prepared cyclopropoxides provides a new synthetic method for ring expansion of the and ring systems.Cyclopropanation of the trimethylsilyl enol ethers derived from a variety of polycyclic ketones affords the required cyclopropyl silyl ethers, which may be ketonized directly or hydrolyzed to the corresponding cyclopropanols before ketonization.The results for fourteen examples serve to define the scope of the ring expansion process, and the silyl enol ethers, cyclopropyl silyl ethers, and most of the corresponding cyclopropanols have been characterized by (13)Cmr.The stereochemistry of the ketonization leading to ring expansion has been established by deuterium labelling experiments.
Synthesis of Norbornanones with a Geminal Dimethyl Group
Buchbauer, Gerhard,Dworan, Erich
, p. 1165 - 1174 (2007/10/02)
The synthesis of gem-dimethylnorbornanones is described.One synthetic pathway after a Diels-Alder reaction involves the transformation of the nitro group into the oxo group with subsequent methylation into the geminal dimethyl product.A shorter way by -cycloaddition of cyclopentadiene with a suitable dimethylated dienophile (e.g. 2-methyl-1-nitropropene) failed, probably by steric hindrance of the dienophile. 7-Oxanorbornanones with a gem -dimethyl group could not be prepared.A second synthetic approach to gem-dimethylnorbornanones is opened by Lewis acid catalyzed rearrangement of cyclohexenylcarbaldehydes. - Keywords: Camphenilone; Diels-Alder reaction; Homonorbornanone; α-Methylation of carbonyls; Nef-reaction; Norepifenchone
A new preparative ring expansion for bicyclic ketones. Homoketonization of cyclopropoxide analogs
Hoyano, Yumiko,Patel Vijay,Stothers, J. B.
, p. 2730 - 2732 (2007/10/02)
Homoketonization of some readily prepared cyclopropoxides affords a new synthetic method for ring expansion of the and ring systems.
