Copper Bis(oxazoline)‐Catalyzed Enantioselective Alkynylation of Benzopyrylium Ions
作者:Yong Guan、Jonathan W. Attard、Anita E. Mattson
DOI:10.1002/chem.201904822
日期:2020.2.6
stereocontrolled construction of biologically relevant chromanones and tetrahydroxanthones has been achieved through the addition of alkynes to benzopyrylium trilfates under the influence of copper bis(oxazoline) catalysis. Excellent levels of enantiocontrol (63-98 % ee) are achieved in the addition of a variety of alkynes to an array of chromenones with a hydrogen in the 2-position. Promising levels of
B(C<sub>6</sub>F<sub>5</sub>)<sub>3</sub>-catalyzed divergent cyanosilylations of chromones dependent on temperature
作者:Qiaotian Wang、Xiangqing Feng、Wei Meng、Haifeng Du
DOI:10.1039/c9ob01710k
日期:——
A B(C6F5)3-catalyzed divergent cyanosilylation of chromones dependent on temperature has been realized to afford the corresponding products in good to high yields.
A B(C6F5)3催化的取决于温度的分歧氰硅化反应已经实现,以获得相应的产物,产率在良好到高收率之间。
Substituent-Oriented Synthesis of Substituted Pyrazoles/Chromeno[3,2-<i>c</i>]pyrazoles via Sequential Reactions of Chromones/3-Chlorochromones and Tosylhydrazones
作者:Tianzi Dai、Qunyi Li、Xiaofei Zhang、Chunhao Yang
DOI:10.1021/acs.joc.9b00282
日期:2019.5.3
A facile and efficient synthetic strategy for the chemoselective synthesis of monocyclic/tricyclic-fused pyrazoles was developed, and it was oriented by different 3-position substituents (H or Cl) on the chromones. The reaction proceeded in a one-pot sequential way with a broad substrate scope and moderate to excellent yields.