Synthesis of masked haloareneboronic acids via iridium-catalyzed aromatic C–H borylation with 1,8-naphthalenediaminatoborane (danBH)
作者:Noriyuki Iwadate、Michinori Suginome
DOI:10.1016/j.jorganchem.2008.11.068
日期:2009.5
"Masked" areneboronic acids have been prepared by Ir-catalyzed C-H borylation of arenes. A [Ir(OMe)(cod)](2) complex with a DPPE ligand showed the highest catalytic activity in the C-H borylation of benzene at 80 degrees C. The reaction system can be applied to substituted arenes, including halogen-substituted arenes. 1,3-Dihalobenzenes undergo the C-H borylation at their 5-positions in a regioselective fashion, affording 3,5-dihaloareneboronic acid derivatives, which serve as useful coupling modules for the convergent dendrimer synthesis. (C) 2008 Elsevier B.V. All rights reserved.
A direct metal-freetransformation from arylamines to aryl naphthalene-1,8-diamino boronamides, a type of masked boronic acid, has been developed based on Sandmeyer-type reactions. A nonsymmetrical diboron reagent, B(pin)-B(dan), was utilized as the borylating reagent, and the B(dan) moiety was transferred to the aim products selectively. This conversion tolerated a series of functional groups, including
An environment-friendly methodology for the synthesis of R (alkyl or aryl)-B(dan) on water is described. 1,8-diamino naphthalene(danH2) was reacted with different types of organoboronic acids to furnish the products in moderate to excellent yields. A multi-gram scale reaction is also performed to ensure the scalability of the reaction.