Palladium-Catalyzed Cocyclotrimerization of Allenes with Arynes: Selective Synthesis of Phenanthrenes
作者:Yi-Lin Liu、Yun Liang、Shao-Feng Pi、Xiao-Cheng Huang、Jin-Heng Li
DOI:10.1021/jo900117c
日期:2009.4.17
Palladium-catalyzed cocyclotrimerization of allenes with arynes has been developed for selectively synthesizing phenanthrenes. In the presence of [(allyl)PdCl]2 and P(o-tol)3, a variety of allenes, including internal and terminal allenes, underwent the cocyclotrimerization with arynes to afford the corresponding phenanthrenes in moderate to good yields. The results showed the selectivity of the reaction
routes have been developed to construct its skeleton. However, synthesis of unsymmetric phenanthrenes remains a challenge. Here, an efficient one-pot tandem reaction for the preparation of phenanthrenes via sequential γ-C(sp2)–H arylation, cationic cyclization, dehydration, and 1,2-migration was developed. A wide range of symmetric and unsymmetric phenanthrenes with diversified functional groups were synthesized
Direct One-Pot Synthesis of Phenanthrenes via Suzuki−Miyaura Coupling/Aldol Condensation Cascade Reaction
作者:Young Ha Kim、Hyuk Lee、Yeong Joon Kim、Bum Tae Kim、Jung-Nyoung Heo
DOI:10.1021/jo702001n
日期:2008.1.1
We have developed an efficient cascade reaction, a Suzuki−Miyaura coupling followed by an aldolcondensation, for the construction of phenanthrene derivatives using microwave irradiation. For example, the reaction of methyl 2-bromophenylacetamide with 2-formylphenylboronic acid in the presence of a palladium catalyst and a base provided a biaryl intermediate, which underwent in situ cyclization to
Synthesis of 9,10-Phenanthrenes via Palladium-Catalyzed Aryne Annulation by <i>o</i>-Halostyrenes and Formal Synthesis of (±)-Tylophorine
作者:Tuanli Yao、Haiming Zhang、Yanna Zhao
DOI:10.1021/acs.orglett.6b00558
日期:2016.6.3
A novel palladium-catalyzedannulation reaction of in situ generated arynes and o-halostyrenes has been developed. This methodology affords moderate to excellent yields of substituted phenanthrenes and is tolerant of a variety of functional groups such as nitrile, ester, amide, and ketone. This annulation chemistry has been successfully applied to the formal total synthesis of a biologically active