Mechanism-Based Design and Optimization of a Catalytic Electrophilic Cyclopropanation
without Diazomethane
Augustin
A. S. W. Tchawou
Mihai Raducan
Peter Chen
10.1021/acs.organomet.6b00531.s001
https://acs.figshare.com/articles/journal_contribution/Mechanism-Based_Design_and_Optimization_of_a_Catalytic_Electrophilic_Cyclopropanation_without_Diazomethane/3520184
Iodomethylboron compounds, either
the trifluoroborate or a boronic
ester, cyclopropanate electron-rich olefins and unprotected allylic
alcohols with Pd catalysts according to a novel, designed catalytic
cycle. Proposed intermediates in a “diverted Heck” mechanism
are observed by means of spectroscopic studies and by isolation and
X-ray crystallographic characterization, which together with reaction
kinetics point to a separation of rate-determining and product-determining
steps, and a mechanism-based optimization of the yield, selectivity,
and scope of the catalytic electrophilic cyclopropanation. The reaction
with crystalline, air-stable, nonhygroscopic, and nontoxic reagents
provides an alternative to Simmons–Smith-type reactions, as
well as cyclopropanation procedures that require the use of diazomethane.
2016-08-04 18:50:13
spectroscopic studies
cyclopropanation procedures
electrophilic cyclopropanation
boronic ester
reaction kinetics point
Catalytic Electrophilic Cyclopropanation
Diazomethane Iodomethylboron compounds
allylic alcohols
Pd catalysts