Guptill DM, Davies HM. L * Emory University, Atlanta, USA
2,2,2-Trichloroethyl Aryldiazoacetates as Robust Reagents for the Enantioselective
C–H Functionalization of Methyl Ethers.
J. Am. Chem. Soc. 2014;
136: 17718-17721
Key words
rhodium - C–H functionalization - carbene insertion
Significance
The asymmetric site-selective functionalization of unactivated sp3 C–H bonds is one of the most challenging reactions to date. Davies and co-workers
demonstrated in this article the utility of trichloroethyl aryldiazoacetates as excellent
substrates in the Rh-catalyzed enantioselective functionalization of methyl ethers.
Comment
A wide spectrum of methyl ethers can be functionalized with trichloroethyl aryldiazoacetates
with moderate and good yields and excellent enantioselectivities. In all cases, regioselectivity
of the carbene insertion is on the less hindered methyl moiety. When a chiral ether
was utilized, different diastereomeric products could be selectively accessed using
opposite enantiomers of the chiral catalyst (matched and mismatched).
