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The stereospecific Fe-catalyzed arylation of enol tosylates was reported. Various tri- or tetrasubstituted Z or E-enol tosylates of β-keto esters were arylated using common and Knochel-type Grignard reagents with complete stereofidelity. The precursors for Z/E-zimelidine, tamoxifen and other bioactive compounds were facilely prepared without precious and toxic transition metals. [ABSTRACT FROM AUTHOR]

Herein we report a room temperature Fe‐catalyzed coupling reaction of various bromophenols with aryl Grignard reagents, which exhibits a wide substrate scope and high functional group tolerance. For the first time, the combination of simple Fe(acac)3/PBu3/Ti(OEt)4 has been used as an effective catalyst for the biaryl couplings of bromophenols or their Na or K salts with debromination and etherification side reactions being well suppressed. Various biphenols including natural product garcibiphenyl C as well as pharmaceutical diflunisal and its ethyl ester were facilely synthesized using the present protocol. [ABSTRACT FROM AUTHOR]

The unprecedented substitution of a nitro group with aryl or alkenyl groups of Grignard reagents affords 2-aryl or alkenylpyridine N-oxides in modest to high yields with high chemoselectivity. This protocol allows a simple and clean synthesis of various 2-substituted pyridine N-oxides and the corresponding pyridine derivatives. Furthermore, straightforward one-pot iterative functionality of pyridine N-oxides could also be achieved simply by successive applications of two Grignard reagents. [ABSTRACT FROM AUTHOR]

For the first time mixed diaryl titanates are used as intermediates to modify the reactivity of the Grignard reagents. [ABSTRACT FROM AUTHOR]

The article presents chemical equations from the article "1, 2-Addition of Alkyl Grignard Reagents to the Nitro Group: Simple Access to 2-[Alkyl (hydroxy) amino] pyridine N-Oxides and 2-Alkylaminopyridine N-Oxides" by F. Zhang and others in the "European Journal of Organic Chemistry" in 2013.

The new method presented here works efficiently with various halopyridine N-oxides and Grignard reagents tolerating a wide range of functional groups. [ABSTRACT FROM AUTHOR]