Iron Catalysis of C(sp)-H Azidation Using a Heteroarene Radical Cation Strategy.

The Fe(phen) catalysis of the benzylic C(sp)-H azidation of indoles has been investigated. The Fe(III) complex can selectively oxidize indoles to form arene radical cations, which are transformed into benzylic C(sp) radical intermediates. This strategy exhibits a difference in reactivity between -heteroarenes and benzene, which is difficult to achieve via direct hydrogen abstraction approaches.

2,3-Difunctionalized Benzo[]thiophene Scaffolds Possessing Potent Antiangiogenic Properties.

A new class of 2-anilino-3-cyanobenzo[]thiophenes (2,3-ACBTs) was studied for its antiangiogenic activity for the first time. One of the 2,3-ACBTs inhibited tubulogenesis in a dose-dependent manner without any toxicity. The 2,3-ACBTs significantly reduced neovascularization in both and angiogenic assays without affecting the proliferation of endothelial cells.

Triflic acid-mediated N-heteroannulation of β-anilino-β-(methylthio)acrylonitriles: a facile synthesis of 4-amino-2-(methylthio)quinolines.

Various functionalised 4-amino-2-(methylthio)quinolines are synthesised through triflic acid-mediated N-heteroannulation of α-functionalized-β-anilino-β-(methylthio)acrylonitriles for the first time. The N-heteroannulation process is highly chemoselective and has mild reaction conditions. However, this process fails in the absence of the β-methylthio group in the acrylonitriles.

Chemoselective Ullmann Reaction of α-Trisubstituted Thioamides: Synthesis of Novel 2-Iminobenzothiolanes.

New classes of unexplored benzo[]thiolanes are synthesized from trisubstituted thioamides through copper-catalyzed intramolecular -arylation of thioamides for the first time. This method provides good to excellent yields with fully controlled chemoselectivity. Unusually, iminobenzo[]thiolanes are very stable under mild acidic conditions.

Nickel catalyzed site selective C-H functionalization of α-aryl-thioamides.

A catalytic site selective intramolecular C-S bond forming reaction is demonstrated for the first time. The C-H bond functionalization of α-aryl-thioacetanilides was efficiently catalyzed by 2 mol% NiBr2, resulting in valuable 2-aminobenzo[b]thiophenes in moderate to good yields. Furthermore, the selective sp2 C-H bond functionalization over sp3 is exemplified.

Copper Catalyzed Intramolecular N-Arylation of Ketene Aminals at Room Temperature: Synthesis of 2-Amino-3-cyanoindoles.

Various 2-amino-3-cyanoindoles are synthesized through copper catalyzed intramolecular N-arylations of ketene aminals at room temperature for the first time with 60-99% yields within 0.1-2 h. Controlled regioselective N-arylations of unsymmetrical ketene aminals are also studied.

Chemoselective Ullmann coupling at room temperature: a facile access to 2-aminobenzo[b]thiophenes.

Various functionalized 2-aminobenzo[b]thiophenes have been synthesized at room temperature by the Ullmann coupling reaction for the first time. The enantiospecific coupling reaction has been further demonstrated without loss of optical purity. The newly synthesized 2-anilino-3-cyano-benzo[b]thiophenes are transformed into 11-amino-benzothieno[2,3-b]quinolines in the presence of triflic acid.