Hydroxylamines
As Bifunctional Single-Nitrogen Sources
for the Rapid Assembly of Diverse Tricyclic Indole Scaffolds
Liangxin Fan
Jiamao Hao
Jingxun Yu
Xiaojun Ma
Jingjing Liu
Xinjun Luan
10.1021/jacs.0c00403.s007
https://acs.figshare.com/articles/dataset/Hydroxylamines_As_Bifunctional_Single-Nitrogen_Sources_for_the_Rapid_Assembly_of_Diverse_Tricyclic_Indole_Scaffolds/12037482
Conventional approaches on using
hydroxylamine derivatives as single
nitrogen sources, for the construction of <i>n</i>-membered
(<i>n</i> > 3) N-heterocycles, rely upon two chemical
operations
by involving sequential nucleophilic and electrophilic C–N
bond formations. Here, we report a highly efficient cascade of alkyne
insertion/C–H activation/amination for the rapid preparation
of a myriad of tricyclic indoles, in a single-step transformation,
by using bifunctional secondary hydroxylamines. It is noteworthy that
judicious selection of applicable amino agents, for enabling the prior
oxidative addition of aryl iodide to initial Pd(0) species and subsequent
two C–N bonds formation, was the key to the success of this
reaction. Control experiments indicated that a five-membered palladacyclic
intermediate played a crucial role in promoting the final aminative
ring closure.
2020-03-26 20:44:45
insertion
sequential nucleophilic
Rapid Assembly
alkyne
Diverse Tricyclic Indole Scaffolds
Bifunctional Single-Nitrogen Sources
N-heterocycle
hydroxylamine derivatives
aryl iodide
electrophilic
species
control experiments
role
aminative ring closure
five-membered palladacyclic
approach
transformation
chemical operations
activation
construction
formation
tricyclic indoles
bifunctional
nitrogen sources
Hydroxylamine
preparation
cascade
oxidative addition
agent
Pd
bond