Construction of Spirofused Tricyclic Frameworks by NHC-Catalyzed Intramolecular Stetter Reaction of a Benzaldehyde Tether with a Cyclic Enone
作者:Day-Shin Hsu、Chiao-Yun Cheng
DOI:10.1021/acs.joc.9b01403
日期:2019.9.6
hydrogenation. These substrates were then exposed to an N-heterocyclic carbene, whereupon intramolecular Stetterreaction proceeded smoothly to give various spirofused tricyclic 1,4-diketones in 30–87% yields. Furaldehyde and nicotinaldehyde derivatives also participated in the reaction under the Stetter conditions.
The invention is concerned with the compounds of formula (I) and pharmaceutically acceptable salts and esters thereof, wherein X, Q, and R1-R6 are defined in the detailed description and claims. In addition, the present invention relates to methods of manufacturing and using the compounds of formula (I) as well as pharmaceutical compositions containing such compounds. The compounds of formula (I) are antagonists or partial agonists at the CRTH2 receptor and may be useful in treating diseases and disorders associated with that receptor such as asthma.
Synthesis of isocoumarins via palladium catalyzed reactions of methyl 2-(2′, 2′-dibromovinyl)benzoates
作者:Le Wang、Wang Shen
DOI:10.1016/s0040-4039(98)01690-6
日期:1998.10
3-Substituted isocoumarins are synthesized in good to excellent yields via palladium catalyzed coupling of 2-(2′,2′-dibromovinyl)benzoates and organostannanes. The process involves a Stille reaction, and a subsequent annulation reaction.
Rhodium(II)-Catalyzed Cyclization of Bis(N-tosylhydrazone)s: An Efficient Approach towards Polycyclic Aromatic Compounds
作者:Ying Xia、Zhenxing Liu、Qing Xiao、Peiyuan Qu、Rui Ge、Yan Zhang、Jianbo Wang
DOI:10.1002/anie.201201374
日期:2012.6.4
Ahead of the PAC: Polycyclicaromaticcompounds (PACs) can be easily accessed by the combination of Suzuki–Miyaura cross‐coupling and a [Rh2(OAc)4]‐catalyzed carbene reaction using easily available bis(N‐tosylhydrazone)s as intermediates (see scheme; Ts=4‐toluenesulfonyl).