652-04-0Relevant articles and documents
Br?nsted Acid-Catalyzed Carbonyl-Olefin Metathesis: Synthesis of Phenanthrenes via Phosphomolybdic Acid as a Catalyst
Chen, Yi,Liu, Di,Wang, Rui,Xu, Li,Tan, Jingyao,Shu, Mao,Tian, Lingfeng,Jin, Yuan,Zhang, Xiaoke,Lin, Zhihua
, p. 351 - 362 (2022/01/03)
Compared with the impressive achievements of catalytic carbonyl-olefin metathesis (CCOM) mediated by Lewis acid catalysts, exploration of the CCOM through Br?nsted acid-catalyzed approaches remains quite challenging. Herein, we disclose a synthetic protocol for the construction of a valuable polycycle scaffold through the CCOM with the inexpensive, nontoxic phosphomolybdic acid as a catalyst. The current annulations could realize carbonyl-olefin, carbonyl-alcohol, and acetal-alcohol in situ CCOM reactions and feature mild reaction conditions, simple manipulation, and scalability, making this strategy a promising alternative to the Lewis acid-catalyzed COM reaction.
Modular, Metal-Catalyzed Cycloisomerization Approach to Angularly Fused Polycyclic Aromatic Hydrocarbons and Their Oxidized Derivatives
Thomson, Paul F.,Parrish, Damon,Pradhan, Padmanava,Lakshman, Mahesh K.
, p. 7435 - 7446 (2015/08/18)
Palladium-catalyzed cross-coupling reactions of 2-bromobenzaldehyde and 6-bromo-2,3-dimethoxybenzaldehyde with 4-methyl-1-naphthaleneboronic acid and acenaphthene-5-boronic acid gave corresponding o-naphthyl benzaldehydes. Corey-Fuchs olefination followed by reaction with n-BuLi led to various 1-(2-ethynylphenyl)naphthalenes. Cycloisomerization of individual 1-(2-ethynylphenyl)naphthalenes to various benzo[c]phenanthrene (BcPh) analogues was accomplished smoothly with catalytic PtCl2 in PhMe. In the case of 4,5-dihydrobenzo[l]acephenanthrylene, oxidation with DDQ gave benzo[l]acephenanthrylene. The dimethoxy-substituted benzo[c]phenanthrenes were demethylated with BBr3 and oxidized to the o-quinones with PDC. Reduction of these quinones with NaBH4 in THF/EtOH in an oxygen atmosphere gave the respective dihydrodiols. Exposure of the dihydrodiols to N-bromoacetamide in THF-H2O led to bromohydrins that were cyclized with Amberlite IRA 400 HO- to yield the series 1 diol epoxides. Epoxidation of the dihydrodiols with mCPBA gave the isomeric series 2 diol epoxides. All of the hydrocarbons as well as the methoxy-substituted ones were crystallized and analyzed by X-ray crystallography, and these data are compared to other previously studied BcPh derivatives. The methodology described is highly modular and can be utilized for the synthesis of a wide variety of angularly fused polycyclic aromatic hydrocarbons and their putative metabolites and/or other derivatives.
Palladium-catalyzed intramolecular C-H activation: A synthetic approach towards polycyclic aromatic hydrocarbons
Paul, Sunanda,Jana, Rathin,Ray, Jayanta K.
experimental part, p. 1463 - 1468 (2010/08/20)
A simple and convenient synthetic protocol for the construction of polycyclic aromatic hydrocarbons has been developed. A variety of phenanthrene, benzo[c]phenanthrene and chrysene derivatives was synthesized via Pd-catalyzed intramolecular C-H activation followed by acid-catalyzed water elimination.
