One stone two birds: construction of polysubstituted benzenes from the same starting material and precatalyst by switching the active sites of catalyst with different additives
作者:Chun Feng、Xin Wang、Bi-Qin Wang、Ke-Qing Zhao、Ping Hu、Zhang-Jie Shi
DOI:10.1039/c1cc15835j
日期:——
Two different tetrasubstituted benzenes were selectively constructed from the same starting materials by tuning the active sites of the Grubbs second generation catalyst (GC-II) with CuI or AgOTf as the additive.
Synthesis of 8-bromo-5,12-tetracenequinone and 2-bromotetracene derivatives
作者:Chitoshi Kitamura、Naohiro Taka、Takeshi Kawase
DOI:10.1007/s11164-012-0638-2
日期:2013.1
A series of bromotetracenequinones 1 and bromotetracenes 2 were prepared from 4-bromophthalic anhydride. The parent tetracenequinone 1a and tetracene 2a were sparingly soluble in organic solvents. In contrast, dipropyl-substituted tetracenequinone 1b and tetracene 2b were a little more soluble. Preparation of dihexyl-substituted tetracene 2c proved to be difficult. Sonogashira coupling of 1b with trimethylsilylacetylene afforded the corresponding product.