Despite the advances in the field of carbon-halogen bond formation, the straightforward catalytic access to selectively functionalized iodoaryls remains a challenge. Here, we report a one-pot synthesis of ortho-iodobiaryls from aryl iodides and bromides by palladium/norbornene catalysis. This new example of Catellani reaction features the initial cleavage of a C(sp )-I bond, followed by the key formation of a palladacycle through ortho C-H activation, the oxidative addition of an aryl bromide and the ultimate restoration of the C(sp )-I bond.
View Article and Find Full Text PDFThe first example of palladium-catalysed oxidative carbonylation of unprotected α-amino amides to hydantoins is described here. The selective synthesis of the target compounds was achieved under mild conditions (1 atm of CO), without ligands and bases. The catalytic system overrode the common reaction pathway that usually leads instead to the formation of symmetrical ureas.
View Article and Find Full Text PDFIron catalyzed site selective and chelation assisted C-H functionalization in 8-amidoquinolines is achieved. The remote C5-benzoxylation with benzoyl peroxide produced a variety of potentially bioactive 8-arylcarboxamido-5-benzoyloxy quinoline derivatives. The efficiency of the reaction reflects from the wide substrate scope with electronic differentiation on carboxamide and acyl peroxide in addition to tolerance of halo-substitutions on either of the aryls.
View Article and Find Full Text PDFWater-mediated one-pot Mannich type condensation of dibenzo[b,d]furan-2-ol with different amines resulted in a large library of novel 2,3-dihydro-1H-benzo[2,3]benzofuro[4,5-e][1,3]oxazine derivatives in moderate to excellent yields. The ortho-aminomethylation of the dibenzofuranols proceeded smoothly in the presence of various aromatic/aliphatic amines and paraformaldehyde, followed by cyclization. All the newly synthesized tetracyclic 2,3-dihydro-1H-benzo[2,3]benzofuro[4,5-e][1,3]oxazine derivatives were chemically characterized and screened for their cytotoxicity activity by cell viability assay (MTT test) against three human cancer cell lines and antibacterial activity by determining the minimum inhibitory concentration (MIC) against four bacterial strains.
View Article and Find Full Text PDFAn unprecedented copper-catalyzed in situ azidation-oxidation for the nitration of anilides and sulfonamides has been developed by direct C-H functionalization. This novel and efficient nitration protocol is achieved employing TMSN and TBHP without the exclusion of air or moisture. The synthetic applications of the 2-nitroanilides have been explored.
View Article and Find Full Text PDFNovel ruthenium complexes (MC113-MC117), obtained by modifying the terpyridine ligand of the black dye (N749), have been evaluated as sensitizers for dye sensitized solar cells (DSSCs). The modification is carried out by attaching selected chromophores, with varying electron donating strength, covalently to the central ring of the ligand. The complexes, compared to the parent dye, show red shifted absorption covering visible and near IR regions and higher molar extinction coefficients.
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