Rhodium(<scp>iii</scp>)-catalyzed indole synthesis at room temperature using the transient oxidizing directing group strategy
作者:Yaping Shang、Krishna Jonnada、Subhash Laxman Yedage、Hua Tu、Xiaofeng Zhang、Xin Lou、Shijun Huang、Weiping Su
DOI:10.1039/c9cc04529e
日期:——
temperature have been developed using an in situ generated N-nitroso group as a transient oxidizing directinggroup. Due to mild reaction conditions, this method enabled synthesis of a broad range of N-alkyl indoles, including even two indole-based medicinal compounds. Our work disclosed the feasibility of the transient oxidizing directinggroup strategy in C–H functionalization reactions, which possesses
Palladium-Catalyzed <i>N</i>-Nitroso-Directed C–H Alkoxylation of Arenes and Subsequent Formation of 2-Alkoxy-<i>N</i>-alkylarylamines
作者:Tingting Gao、Peipei Sun
DOI:10.1021/jo501902d
日期:2014.10.17
A palladium-catalyzed direct ortho-alkoxylation of N-alkyl-N-nitrosoarylamines was developed in which alcohols were used as the alkoxylation reagents and PhI(OAc)2 was employed as the oxidant. The protocol was available for both primary and secondary alcohols. The products were transformed to o-alkoxy-N-alkylanilines expediently by a simple reduction.
Rhodium(III)-Catalyzed<i>N</i>-Nitroso-Directed CH Addition to Ethyl 2-Oxoacetate for Cycloaddition/Fragmentation Synthesis of Indazoles
作者:Jinsen Chen、Pei Chen、Chao Song、Jin Zhu
DOI:10.1002/chem.201404506
日期:2014.10.27
RhIII‐catalyzed N‐nitroso‐directed CH addition to ethyl 2‐oxoacetate allows subsequent construction of indazoles, a privileged heterocycle scaffold in synthetic chemistry, through the exploitation of reactivity between the directing group and installed group. The formal [2+2] cycloaddition/fragmentation reaction pathway identified herein, a unique reactivity pattern hitherto elusive for the N‐nitroso
reported for the denitrosation of aryl-N-nitrosamines under mild reaction conditions using ethanethiol and PTSA. The reactions proceeds at roomtemperature and the amines are obtained in good to excellent yields. Many functional groups that are susceptible to reduction were stable during the denitrosation. A broad substrate scope and easy operations are salient features of this method.
A novel and efficient Rh(III)-catalyzed direct C–H bond tandem annulation of N-nitrosoanilines with 1,3-dicarbonylcompounds through two C–H bond cleavage was developed. This protocol provides a rapid access to a series of valuable tetrahydrocarbazol-4-ones with the feature of readily available starting materials, broad functional group tolerance, and in situ generation of carbene precursors. Importantly