Tetrabutylammonium Bromide (TBAB) Promoted Metal-Free Synthesis of 2H-Indazolo[1,2-b]Phthalazinetriones and Pyrazolo[1,2-b]Phthalazines from Benzylalcohol through Aerobic Oxidation, Sequential Addition-Cyclization with Phthalhydrazide and β-Diketones

One-Pot Sequential Synthesis of Alkenylated Dihydroquinolinones and Hexahydroacridinones in Deep Eutectic Solvent Medium

The sequential synthesis of N-heterocycles from saturated ketones poses significant challenges and has rarely been reported. Herein, an efficient synthesis of alkenylated dihydroquinolinones 7 and hexahydroacridinones 8 is achieved from saturated ketones 1 or 2 via dehydrogenation, cyclization, oxidation, and α-alkenylation in choline chloride-based deep eutectic solvent (DES) medium. This strategy provides alkenylated dihydroquinolinones 7 and hexahydroacridinones 8 in excellent yield from low-cost, readily available starting materials under environmentally benign conditions. Furthermore, the synthesized compounds (4, 5, 7, and 8) were investigated for their photophysical properties through absorption and emission spectral studies.

A Cu2O/TBAB-promoted approach to synthesize heteroaromatic 2-amines via one-pot cyclization of aryl isothiocyanates with ortho-substituted amines in water

An efficient approach to synthesize heteroaromatic 2-amines from one-pot desulfurization/dehydrogenative cyclization of aryl isothiocyanates with ortho-substituted amines in water was developed. This approach tolerated a wide range of functional groups on the aromatic ring, providing a practical and environment-friendly process to synthesize heteroaromatic 2-amines in moderate to excellent yields. A plausible mechanism was proposed and the role of TBAB and Cu2O in the present strategy was suggested with the help of ESI mass spectrometry.