53156-66-4Relevant academic research and scientific papers
Synthesis of Polycyclic Spirocarbocycles via Acid-Promoted Ring-Contraction/Dearomative Ring-Closure Cascade of Oxapropellanes
Ogawa, Naoki,Yamaoka, Yousuke,Takikawa, Hiroshi,Takasu, Kiyosei
, p. 7563 - 7567 (2019)
We report herein the development of an acid-promoted rearrangement of oxa[4.3.2]propellanes to afford polyaromatic-fused spiro[4.5]carbocycles. DFT calculations suggest that the reaction pathway involves generation of a cyclobutyl cation, ring contraction
Exploiting the π-acceptor properties of carbene-stabilized phosphorus centered trications [L3P] 3+: Applications in Pt(II) catalysis
Carreras, Javier,Patil, Mahendra,Thiel, Walter,Alcarazo, Manuel
, p. 16753 - 16758,6 (2012/12/13)
Reaction of tris(dimethylaminocyclopropenium) substituted phosphine 1 with K2PtCl4 afforded the bench stable complex 3 which upon treatment with Ag[CB11H6Cl6] turned out to be an excellent catalyst for the transformation of a variety of ortho-biaryl substituted alkynes into polycyclic homo- and heteroarenes of different size, shape, and curvature through a 6-endo-dig cyclization. This constitutes the first example ever reported of using a P1-centered trication as ligand in catalysis. The strong π-acceptor character of 1 that derives from its three positive charges substantially increases the intrinsic π-acidity of Pt in complex 1?PtCl2 and dramatically enhances its ability to activate π-systems toward nucleophilic attack. As a consequence, a remarkable acceleration of the model transformation is observed when compared with other classical π-acceptor ligands such as P(OPh)3 or P(C 6F5)3. Moreover, the employment of 1 as ligand also expands the scope of this reaction to previously inaccessible substitution patterns. Kinetic studies and deuterium labeling experiments as well as density functional theory (DFT) calculations were performed in order to explain these findings.
Partitioning of Charge in Dibenzochrysene: The Role of the System's Topology
Zelikovich, Lior,Hoffman, Roy E.,Ayalon , Ari,Rabinovitz, Mordecai
, p. 1785 - 1792 (2007/10/02)
Dibenzochrysene dianion (32-) shows in its NMR spectrum a partitioning of charge.In the dianion most of the charge is located on the 'anthracene' moiety.These observations have been confirmed by MNDO calculations.In the calculations, the l
