Improved Syntheses and Some Selective Transformations of 2,2,4,4-Tetrachloro-8-oxabicyclo[3.2.1]oct-6-en-3-ones
作者:Stefan Sendelbach、Rüdiger Schwetzler-Raschke、Andreas Radl、Roland Kaiser、Gerhard H. Henle、Hilmar Korfant、Stefan Reiner、Baldur Föhlisch
DOI:10.1021/jo972037g
日期:1999.5.1
couple leads to the corresponding oxabicyclic ketones 4. On catalytic hydrogenation of the tetrachlorooxabicyclooctenones 3a-c hydrogenolysis of the exo-carbon-chlorine bonds occurs, leading to the endo-2,endo-4-dichloro-8-oxabicyclooctan-3-ones 8a-c. With lithiumaluminumhydride and Grignard reagents, 8a and 3a form the endo-3-alcohols 12a-c and 13, respectively, the latter with uncertain configuration
Cyclopentannulation reactions with organoiron reagents. Facile construction of functionalized hydroazulenes
作者:M. Rosenblum、J. C. Watkins
DOI:10.1021/ja00173a020
日期:1990.8
ketohydroazulene cycloadducts derived, in each reaction, from a single tautomeric tropyllium cation. The further reaction of two such cycloadducts with lithium dimethyl cuprate gave tricyclic ketones, through a sequence depicted as involving initial formation of an anionic acyliron complex, followed by migratory insertion and an intramolecular aldolcondensation
Electrochemically induced transformation of 4(6)-dihalomethyl-4(6)-methylcyclohexa-2,5(2,4)-dien-1-ones into 4(2)-methyltropones
作者:A. A. Moiseeva、G. V. Gavrilova、E. K. Beloglazkina、D. M. Krut’ko、N. V. Zyk
DOI:10.1134/s1070363211080135
日期:2011.8
Electrochemical investigation of 4(6)-dihalomethyl-4(6)-methylcyclohexa-2,5(2,4)-dien-1-ones using cyclic voltammetry (CVA) and rotating disc electrode (RDE) methods has been performed. The reductive dehalogenation of cyclohexa-2,5(2,4)-dien-1-ones having a dihalomethyl substituent at the tertiary carbon atom was shown to proceed as a two-electron reductive elimination of the geminal halogen atoms
Photoreactions of 4-(Tribromomethyl)-4-methyl-2,5-cyclohexadienone and Its Derivatives with Amines: Radical Cyclization and Ring Expansion Reactions Promoted through Photoinduced Electron Transfer Processes
Photoreactions of 4-(tribromomethyl)-4-methyl-2,5-cyclohexadienone (1) and its derivatives with amines were studied. Irradiation of 1 with amine produced 4-bromo-5-methyltropone (2) along with 4-(dibromomethyl)-4-methyl-2,5-cyclohexadienone (3). The effects of solvent, added water, and the structural variation in amine on the product ratio were explored. Isolation of the amine-derived products revealed
New version of redox-troponization ? oxidative expansion of apara-semiquinoid ring in the reaction of 4-methyl-4-bromomethyl-2,5-cyclohexadien-1-one with tetrakis(triphenylphosphine)palladium
作者:V. A. Nikanorov、G. V. Gavrilova、A. V. Yur'ev、V. I. Rozenberg、O. A. Reutov
DOI:10.1007/bf01151309
日期:1995.9
Abstract4-Methyl-4-bromomethyl-2,5-cyclohexadien-1-one reacts with Pd(PPh3)4 in benzene to give 4-methyl-2,4,6-cycloheptatrien-1-one. The reaction occurs as intramolecular carbometallation of the enone fragment of the starting dienone followed by rearrangement—dehydrometallation or involves a sequence of steps,viz., homolytic abstraction of the halogen atom, cyclization, recyclization, and dehydrogenation