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A chemoselective C−N coupling (Buchwald‐Hartwig‐type) reaction of diarylamines with aryl halides bearing non‐protected amino or hydroxy groups proceeds in the presence of a simple iron catalyst. Upon treatment with Grignard reagents, various diarylamines can be cross‐coupled with halocarbazoles, haloindoles, haloanilines, and halophenols to afford the corresponding triarylamines, without the undesired dimerization or oligomerization of the starting aryl halides. DFT studies on the dimeric iron amide intermediates reveal that the reductive elimination can be the selectivity determining step. Finally, a short‐step synthesis of a thermally activated delayed‐fluorescence emitter, DACT‐II, demonstrates the synthetic utility of the present method. [ABSTRACT FROM AUTHOR]

The first iron-catalysed enantioselective Suzuki–Miyaura coupling reaction has been developed. In the presence of catalytic amounts of FeCl2 and (R,R)-QuinoxP*, lithium arylborates are cross-coupled with tert-butyl α-bromopropionate in an enantioconvergent manner, enabling facile access to various optically active α-arylpropionic acids including several nonsteroidal anti-inflammatory drugs (NSAIDs) of commercial importance. (R,R)-QuinoxP* is specifically able to induce chirality when compared to analogous P-chiral ligands that give racemic products, highlighting the critical importance of transmetalation in the present asymmetric cross-coupling system. [ABSTRACT FROM AUTHOR]

Reported is the anti-selective carbosilylation of internal alkynes with silylborane and alkyl halides using a FeBr2/DPPE catalyst system. The iron catalyst allows simultaneous introduction of a carbon electrophile and a silicon nucleophile to simple internal alkynes, including diaryl-, dialkyl-, and aryl/alkyl-substituted alkynes, in a highly stereoselective manner. Alkyl halides are applicable as the electrophiles, thereby enabling the synthesis of a variety of tetrasubstituted alkenylsilanes. In addition, syn-selective carbosilylation was achieved through stereoswitching, by using a silylborane having oxygen functionality on the silyl group. This novel iron-catalyzed carbosilylation is a useful tool for expedient synthesis of stereodefined multisubstituted olefins, a fundamental structural motif in organic chemistry. [ABSTRACT FROM AUTHOR]

A catalytic amount of 1,2-bis(diphenylphosphino)benzene (DPPBz) achieves selective cleavage of sp3-carbon-halogen bond in the ironcatalysed cross-coupling between polyfluorinated arylzinc reagents and alkyl halides, which was unachievable with a stoichiometric modifier such as TMEDA; the selective iron-catalysed fluoroaromatic coupling provides easy and practical access to polyfluorinated aromatic compounds. [ABSTRACT FROM AUTHOR]

Abstract: In our hands, Fe(II) or (III) pyridine complexes show no activity in Suzuki biaryl cross-coupling reactions, except in one irreproducible instance when complete conversion was observed. A comparison with palladium acetate under the same conditions showed that complete conversion can be obtained in a S:C ratio of 1,000,000:1 and therefore extreme caution must be exercised to prevent ‘false-positives’ arising from trace Pd-contaminants. [Copyright &y& Elsevier]

The article focuses on the iron-catalyzed cross-coupling of primary and secondary alkyl halides with aryl Grignard reagents. It has been reported that iron catalysis allows to achieve cross-coupling between near stoichiometric amounts of an alkyl halide and an aryl Grignard reagent generally in excellent yield. The use of iron provides obvious practical and environmental merits, and the method allows the use of rather unreactive secondary bromides and chlorides on a synthetically useful scale. A useful feature of the present reaction is the compatibility of functional groups such as alkoxycarbonyl and N-indolyl group as well as alkenyl and alkynyl groups in the alkylating reagent survive under the reaction.

Abstract: Optimum reaction conditions are examined for the intramolecular ring closing C—N bond formation affording six 5,10‐diaryl‐5,10‐dihydrophenazines of type (II).They can find potential use as hole‐injection materials in organic electroluminescence devices. [ABSTRACT FROM AUTHOR]

The practical and simple protocol provides α-arylalkanoates in moderate to high yields and with often high enantiomeric excess. [ABSTRACT FROM AUTHOR]

Novel iron-catalyzed amination reactions of various aryl bromides have been developed for the synthesis of diaryl- and triarylamines. The key to the success of this protocol is the use of in situ generated magnesium amides in the presence of a lithium halide which dramatically increases the product yield. The present method is simple and free of precious and expensive metals and ligands thus providing a facile route to triarylamines a recurrent core unit in organic electronic materials as well as pharmaceuticals. [ABSTRACT FROM AUTHOR]

In the presence of novel iron(ll) chioride-diphosphine complexes and magnesium bromide, lithium arylborates react with primary and secondary alkyl halides to give the corresponding coupling products ri good to excellent yields. High functional group compatibility is also demonstrated in the reactions of substrates possessing reactive substituents, such as alkoxycarbonyl, cyano, and carbonyl groups. [ABSTRACT FROM AUTHOR]

The article presents a study that investigates the effect of tetramethylethylenedianmine (TMEDA) on iron-catalyzed coupling reaction of ArMgX with alkyl halides. The study was conducted by assessing the various types of Grignard reagents and its iron-catalyzed reaction were identified using nuclear magnetic resonance (NMR) spectroscopy. The study reveals that TMEDA can establish coordination with iron to create catalytic cycle that serve as basis of design for iron-catalyzed coupling reactions.

Review: 190 refs. [ABSTRACT FROM AUTHOR]