2568-17-4Relevant academic research and scientific papers
Synthesis, Molecular Structure, and Chiroptical Properties of Dibenzylidene Derivatives of Bicyclo[3.3.1]nonane and Brexane
Ston?ius, Sigitas,Neni?kis, Algirdas,Loganathan, Nagarajan,Wendt, Ola F.
, p. 728 - 737 (2015/10/12)
Synthesis of several enantiomerically pure unsaturated bicyclo[3.3.1]nonane and related brexane (tricyclo[4.3.0.03,7]nonane) derivatives bearing exocyclic benzylidene substituents from readily available (+)-(1S,5S)-bicyclo[3.3.1]nonane-2,6-dione was accomplished. Molecular geometry and chiroptical properties of compounds with enone and styrene chromophores were studied by X-ray diffraction analysis, molecular modeling, and circular dichroism (CD) spectroscopy. Difunctional 3,7-dibenzylidenebicyclo[3.3.1]nonanes, such as 2 and 7, 8, 9, exhibited intense CD couplets, arising from the exciton coupling between the two unsaturated chromophores. The observed negative sign of the exciton couplets is congruent with the negative twist (negative chirality) defined by the two interacting transition dipoles. The sign of the Cotton effect corresponding to the π→π? transitions in the CD spectra of monoenone 4 and tricyclic brexane acetate 11 was correlated with the intrinsic dissymmetry (helicity) of the styrene chromophore. Chirality 27:728-737, 2015.
Homoconjugation and transannular orbital interactions detected by photoelectron and13C-NMR spectroscopy. Bicyclo[3.3.1]nona-3,7-diene-2,6-dione and bicyclo[3.3.1]nonane-2,6-dione
Doerner, Thomas,Gleiter, Rolf,Robbins, Timothy A.,Chayangkoon, Paochai,Lightner, David A.
, p. 3235 - 3241 (2007/10/02)
Transannular orbital interactions between two ketone carbonyl groups located at positions 2 and 6 on the bicyclo[3.3.1]nonane carbocyclic framework were detected by 13C-NMR and photoelectron spectroscopy (PES). Thus, an ～4.4-ppm shielding of th
Preparation of Bicyclononane-2,4-dione Derivatives
Inouye, Yoshinobu,Kojima, Tsutomu,Owada, Jun,Kakisawa, Hiroshi
, p. 4369 - 4376 (2007/10/02)
Bicyclononane-2,4-dione and 7-endo-benzyloxy-9-methylenebicyclononane-2,4-dione were prepared starting from bicyclononan-2-one and 7-endo-benzyloxybicyclononane-2,9-dione, respectively.The key reaction was the NCS oxidation of the 2,2-ethylenedioxy-4-phenylthiobicyclononanes, derived from the corresponding bicyclonon-3-en-2-ones.
SYNTHESIS OF A (+/-)-3β-TRINORTAXANE DERIVATIVE
Kojima, Tsutomu,Inouye, Yoshinobu,Kakisawa, Hiroshi
, p. 323 - 326 (2007/10/02)
Intramolecular photo cycloaddition of 4-(3-methyl-2-cyclohexenyl)methoxybicyclo non-3-en-2-one, followed by oxydation with RuO4 and by alkaline hydrolysis, gave 8-methyl-tricyclo3,8>pentadecane-2,10-dione-4-carboxylic acid,
Intramolecular Reactions Involving Positions C(2), C(6) and C(2), C(7) in the Bicyclononane Ring System
Bishop, Roger,Parker, William,Stevenson, James Ronald
, p. 565 - 573 (2007/10/02)
Reactions likely to involve C(2)-C(6) and C(2)-C(7) intramolecular reactions in bicyclononane derivatives are discussed in terms of the conformations available to the ring system.While endo-6-hydroxybicyclononan-2-one (11) incorporated three deuterium atoms (excluding the hydroxy-group) on heating with NaOD, the exo-isomer (17) exchanged the six hydrogens adjacent to the oxygenation functions but not the carbinyl proton.Evidence is presented favouring a stereospecific base-induced 2,6-hydride migration, most probably proceeding via a twin-twist boat transition state.Treatment of 6,6-ethylenedioxy-2-methoxymethylenebicyclononane (36) with aqueous HCl in acetone produced 2-hydroxyprotoadamantan-10-one (38) in high yield.This process resulted from hydrolysis of the oxygenated groups thereby liberating the endo-keto-aldehyde intermediate (37) which underwent subsequent intramolecular aldol condensation between the C(2) aldehyde and C(7).
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.
