1581719-80-3Relevant academic research and scientific papers
Rhodium-catalyzed C-H alkynylation of arenes at room temperature
Feng, Chao,Loh, Teck-Peng
, p. 2722 - 2726 (2014/03/21)
The rhodium(III)-catalyzed ortho C-H alkynylation of non-electronically activated arenes is disclosed. This process features a straightforward and highly effective protocol for the synthesis of functionalized alkynes and represents the first example of merging a hypervalent iodine reagent with rhodium(III) catalysis. Notably, this reaction proceeds at room temperature, tolerates a variety of functional groups, and more importantly, exhibits high selectivity for monoalkynylation. Hot rhod: A rhodium-catalyzed, electronically reversed Sonogashira reaction between unbiased arenes and the hypervalent iodine reagent 1 proceeds through C-H activation. This reaction displays excellent functional-group tolerance and high efficiency, and thus opens a new synthetic pathway to access functionalized alkynes. Cp=C5Me5, DCE=1,2-dichloroethane, Piv=pivaloyl, TIPS=triisopropylsilyl.
Rh(III)- and Ir(III)-Catalyzed C-H alkynylation of arenes under chelation assistance
Xie, Fang,Qi, Zisong,Yu, Songjie,Li, Xingwei
supporting information, p. 4780 - 4787 (2014/04/17)
An efficient Rh(III)- and Ir(III)-catalyzed, chelation-assisted C-H alkynylation of a broad scope of (hetero)arenes has been developed using hypervalent iodine-alkyne reagents. Heterocycles, N-methoxy imines, azomethine imines, secondary carboxamides, azo compounds, N-nitrosoamines, and nitrones are viable directing groups to entail ortho C-H alkynylation. The reaction proceeded under mild conditions and with controllable mono- and dialkynylation selectivity when both mono- and dialkynylation was observed. Rh(III) and Ir(III) catalysts exhibited complementary substrate scope in this reaction. The synthetic applications of the coupled products have been demonstrated in subsequent derivatization reactions. Some mechanistic studies have been conducted, and two Rh(III) complexes have been established as key reaction intermediates. The current C-H alkynylation system complements those previously reported under gold or palladium catalysis using hypervalent iodine reagents.
