Cycloaromatization via Ruthenium-Allenylidene Complexes

Transition-Metal-Mediated Aromatic Ring Construction, First Edition. Edited by Ken Tanaka. 2013 John Wiley Sons, Inc. Published 2013 by John Wiley Sons, Inc. 

Transition-metal-catalyzed direct arylation of arenes with aryl halides via cleavage of aryl C—H bonds serves as a straightforward method for aryl-aryl bond formation [3], Hence, direct arylation of two aromatic rings tethered by aromatic/alkenyl moieties or heteroatoms (i.e. intramolecular variant of the direct arylation) constitute efficient syntheses of PAHs such as benzofurans, carbazoles, dibenzothiophenes, dibenzosiloles, and phenanthrenes. In this section we overview the progress with subsections categorized by product structures [5]. 

SCHEME 22.1 Intramolecular direct arylation of aryl 2-bromophenyl ethers. 

SCHEME 22.2 Intramolecular direct arylation of brominated/chlorinated diaryl ethers and diarylamines. 

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