β-Arylation of Carboxamides via Iron-Catalyzed C(sp3)–H Bond Activation
摘要:
A 2,2-disubstituted propionamide bearing an 8-aminoquinolinyl group as the amide moiety can be arylated at the beta-methyl position with an organozinc reagent in the presence of an organic oxidant, a catalytic amount of an iron salt, and a biphosphine ligand at 50 degrees C. Various features of selectivity and reactivity suggest the formation of an organometallic intermediate via rate-determining C-H bond cleavage rather than a free-radical-type reaction pathway.
diverse five‐membered lactams from aliphaticamides and terminal acetylenes with the assistance of an 8‐aminoquinolyl auxiliary has been achieved. A broad range of terminal acetylenes and aliphaticamides proved to be the efficient coupling partners, furnishing the corresponding lactams in moderate to good yields. The transformation is proven to undergo an oxidative alkynylation followed by the intramolecular
by Pd-catalyzed C(sp3)–H bond functionalization was developed. Using a bidentate directing group, the direct and selective introduction of a SCF3 moiety was possible on a range of amides with remarkable selectivity for C(sp3)-centers with an electrophilic SCF3 source and pivalic acid as an additive. This work constitutes an example of the unactivated C(sp3)–SCF3 bond formation by C–Hactivation offering
Iron-Catalyzed <i>Ortho</i> C–H Methylation of Aromatics Bearing a Simple Carbonyl Group with Methylaluminum and Tridentate Phosphine Ligand
作者:Rui Shang、Laurean Ilies、Eiichi Nakamura
DOI:10.1021/jacs.6b06908
日期:2016.8.17
(Me2N-TP), that allows us to convert an ortho C-H bond to a C-CH3 bond in aromatics and heteroaromatics bearing simple carbonyl groups under mild oxidative conditions. The reaction is powerful enough to methylate all four ortho C-H bonds in benzophenone. The reaction tolerates a variety of functionalgroups, such as boronic ester, halide, sulfide, heterocycles, and enolizable ketones.
A new method of cobalt-catalyzed synthesis of pyrrolidinones from aliphatic amides and terminal alkynes was discovered through a C-Hbond functionalization process on unactivated sp(3) carbons with the silver cocatalyst using a bidentate auxiliary. For the first time, a broad range of easily accessible alkynes are exploited as the reaction partner in C(sp(3))-H bondactivation to give the important
β-C(sp3)–H bonds of propioamides with organosilanes is described. The reaction proceeds with the assistance of an 8-aminoquinolyl auxiliary in a tandem way by the first oxidation of β-C(sp3)–H bonds and subsequent arylation/vinylation to give the aryloxylation/vinyloxylation products. This unusual aryloxy/vinyloxy forming reaction offers a new avenue for the functionalization of unactivated sp3 C–H