Irradiation-Induced
Heck Reaction of Unactivated Alkyl
Halides at Room Temperature
Guang-Zu Wang
Rui Shang
Wan-Min Cheng
Yao Fu
10.1021/jacs.7b10009.s001
https://acs.figshare.com/articles/journal_contribution/Irradiation-Induced_Heck_Reaction_of_Unactivated_Alkyl_Halides_at_Room_Temperature/5616505
The
palladium-catalyzed Mizoroki–Heck reaction is arguably
one of the most significant carbon–carbon bond-construction
reactions to be discovered in the last 50 years, with a tremendous
number of applications in the production of chemicals. This Nobel-Prize-winning
transformation has yet to overcome the obstacle of its general application
in a range of alkyl electrophiles, especially tertiary alkyl halides
that possess eliminable β-hydrogen atoms. Whereas most palladium-catalyzed
cross-coupling reactions utilize the ground-state reactivity of palladium
complexes under thermal conditions and generally apply a single ligand
system, we report that the palladium-catalyzed Heck reaction proceeds
smoothly at room temperature with a variety of tertiary, secondary,
and primary alkyl bromides upon irradiation with blue light-emitting
diodes in the presence of a dual phosphine ligand system. We rationalize
that this unprecedented transformation is achieved by utilizing the
photoexcited-state reactivity of the palladium complex to enhance
oxidative addition and suppress undesired β-hydride elimination.
2017-11-08 00:00:00
ground-state reactivity
alkyl halides
palladium-catalyzed cross-coupling reactions
50 years
oxidative addition
application
undesired β- hydride elimination
eliminable β- hydrogen atoms
palladium complexes
light-emitting diodes
Unactivated Alkyl Halides
room temperature
phosphine ligand system
alkyl bromides
palladium-catalyzed Heck reaction proceeds
Room Temperature
photoexcited-state reactivity
Irradiation-Induced Heck Reaction
ligand system
alkyl electrophiles
Nobel-Prize-winning transformation