Transition-metal-free cross-coupling reaction of benzylic halides with arylboronic acids leading to diarylmethanes

Transition-Metal-Free Direct α-Arylation of Weinreb-type Amides with Arylboronic Acids through Aza-oxyallyl Cation Intermediates

Here, we report an efficient transition-metal-free C(sp2)-C(sp3) Suzuki-Miyaura-type cross-coupling between α-halo Weinreb-type amides and arylboronic acids. The reaction is carried out by capturing active aza-oxyallyl cation (AOAC) with arylboronic acid to form a boron "ate" complex, followed by 1,4-migration to give α-aryl amides with good yields.

Diiodomethane-Mediated Generation of N-Aryliminium Ions and Subsequent [4 + 2] Cycloadditions with Olefins

Herein, we report a method for in situ generation of N-aryliminium ions via reactions of N,N-dimethylanilines with diiodomethane. We used the method to prepare tetrahydroquinolines via one-pot three-component reactions between N,N-dimethylanilines, diiodomethane, and olefins. This transformation involves initial reaction of the aniline with diiodomethane to form an iodomethylammonium salt, which undergoes fragmentation accompanied by elimination of methyl iodide to give an N-aryliminium ion, which is trapped by the olefin via [4 + 2] cycloaddition to give the final product. This method for generating N-aryliminium ions requires neither a catalyst nor a strong oxidant, suggesting that it can be expected to find broad utility, especially for substrates that are sensitive to Lewis acids, transition metals, or strong oxidants.

Applications of sulfuryl fluoride (SO2F2) in chemical transformations

A number of novel methodologies concerning the chemical, biological and medicinal applications of sulfuryl fluoride (SO₂F₂) gas have dramatically improved year by year.

Transition-Metal-Free Synthesis of Biarylmethanes from Aryl Iodides and Benzylic Ketones

An original metal-free procedure for the synthesis of biarylmethanes is disclosed herein. The reactions occur with high selectivity starting from aryl iodides and benzylic ketones in the presence of superbasic media (CsOH/DMSO). This procedure allows a straightforward access to a wide range of biarylmethane derivatives substituted with electron-withdrawing and -donating substituents.

Electron-Catalyzed Cross-Coupling of Arylboron Compounds with Aryl Iodides

Arylboroxines in combination with zinc chloride and potassium tert-butoxide were found to undergo the electron-catalyzed cross-coupling with aryl iodides to give the corresponding biaryls without the aid of transition-metal catalysis.