Readily available phenol-derived biaryls reacted with allenes underpalladiumcatalysis to provide a variety of highly valuable spiro[cyclohexane-1,1′-indene]-2,5-dien-4-ones. This new catalytic process, involving a key step of regioselective allylative dearomatization of phenol, proceeded efficiently through a [3 + 2] spiroannulation pathway by overcoming undesired β-hydride elimination. Preliminary
Recyclable copper catalyzed nitrogenation of biphenyl halides: a direct approach to carbazoles
作者:Yang Ou、Ning Jiao
DOI:10.1039/c3cc41443d
日期:——
A novel A21-CuI catalyzed direct nitrogenation of biphenyl halides for the direct synthesis of carbazoles via a direct C–H amination process has been developed. A recyclable and inexpensive Cu-catalyst was successfully employed in N-heterocyclic compound synthesis via tandem azidation and C–H amination, which makes this protocol very practical and easy to handle.
Construction of
<scp>Alkenyl‐Functionalized</scp>
Spirocarbocyclic Scaffolds from
<scp>Alkyne‐Containing Phenol‐Based</scp>
Biaryls
<i>via</i>
Sequential
<scp>Iodine‐Induced</scp>
Cyclization/Dearomatization and
<scp>Pd‐Catalyzed</scp>
Coupling of
<scp>
<i>N</i>
‐Tosylhydrazones
</scp>
作者:Anjia Liu、Kaiming Han、Xin‐Xing Wu、Shufeng Chen、Jianbo Wang
DOI:10.1002/cjoc.202000170
日期:2020.11
An efficient strategy for the formation of alkenyl‐functionalized spirocarbocyclic scaffolds from alkyne‐containing phenol‐based biaryls via sequential iodine‐induced cyclization/dearomatization and Pd‐catalyzed coupling of N‐tosylhydrazones is developed. The approach provides various spirocarbocyclic compounds in moderate to excellent yields with good functional tolerance. The results also demonstrate
A novel palladium‐catalyzed three‐component reaction of phenol‐derived biaryls with N‐benzoyloxyamines and norbornadiene (NBD) has been developed for the assembly of highly functionalized spiroindenes. This domino process was realized through NBD‐assisted C−H amination and phenol dearomatization by forming one C−N bond and two C−C bonds in a single step. Preliminary studies indicated that asymmetric
A novel Pd(0)-catalyzed intermolecular carbocyclization of phenol-derived biaryls with 1,3-dienes has been implemented through a sequence of oxidativeaddition to the C–I bond, regioselective olefin insertion, and allylative dearomatization. This method provides a broad range of attractive spirocyclic compounds bearing two contiguous tertiary/quaternary carbon centers in good yields with excellent