Entry to 1,2,3,4-Tetrasubstituted Arenes through Addressing the "Meta Constraint" in the Palladium/Norbornene Catalysis.

ABSTRACT: Arenes with four different contiguous substituents, i.e. 1,2,3,4-tetrasubstituted arenes, are commonly found in bioactive compounds, but they are nontrivial to access via conventional methods. Through addressing the "meta constraint" in the palladium/norbornene (Pd/NBE) cooperative catalysis, which is the difficulty of tolerating a sizable meta substituent in aryl halide substrates, here a modular and regioselective approach is realized for preparing 1,2,3,4-tetrasubstituted arenes. One key is the use of a C2-amide-substituted NBE, and a combined experimental and computational study reveals its role in promoting the NBE insertion and the ortho C-H metalation steps. The scope is broad: a variety of electrophiles and nucleophiles could be introduced to the ortho a

SUBMITTER: Wang J 

PROVIDER: S-EPMC7081784 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature