142095-76-9Relevant articles and documents
Sigmatropic Rearrangements of Hypervalent-Iodine-Tethered Intermediates for the Synthesis of Biaryls
Hori, Mitsuki,Guo, Jing-Dong,Yanagi, Tomoyuki,Nogi, Keisuke,Sasamori, Takahiro,Yorimitsu, Hideki
, p. 4663 - 4667 (2018)
Metal-free dehydrogenative couplings of aryliodanes with phenols to afford 2-hydroxy-2′-iodobiaryls have been developed. This reaction proceeds through ligand exchange on the hypervalent iodine atom followed by a [3,3] sigmatropic rearrangement and with complete regioselectivity. This coupling, in combination with in situ oxidation by mCPBA, enables the convenient conversion of iodoarenes into desirable biaryls. The obtained biaryls have convertible iodo and hydroxy groups in close proximity, and are thus synthetically useful, as exemplified by the controlled syntheses of π-extended furans and a substituted [5]helicene. DFT calculations clearly revealed that the rearrangement is sigmatropic, with C?C bond formation and I?O bond cleavage proceeding in a concerted manner. Acetic acid, which was found to be the best solvent for this protocol, renders the iodine atom more cationic and thus accelerates the sigmatropic rearrangement.
The reactivity of oxygen nucleophiles with aryl radicals in the S(RN)1 mechanism
Baumgartner,Pierini,Rossi
, p. 2323 - 2326 (1992)
The photostimulated reaction of 2-naphthoxide ions 1 with o-dihalobenzenes in liquid ammonia gives the halosubstituted product 4 and the cyclized substituted product 5. This is the first report about the coupling of an aromatic σ radical with an oxygen functionality in the chain propagation cycle of the S(RN)1 mechanism.
