• Bulletin of the Korean Chemical Society
• /
• 제30권8호
• /
• pp.1767-1770
• /
• 2009

The Henry (nitroaldol) reaction proceeds under mild conditions with catalytic amount of tetramethylethylenediamine (TMEDA) to afford $\beta$-nitro alkanol in considerably excellent yield. Structurally diverse aldehydes react with nitromethane in presence of 0.3 equiv of TMEDA under solvent-free condition at rt. The low catalytic loading and mild reaction condition are the key features of the catalytic method.

• Bulletin of the Korean Chemical Society
• /
• 제29권2호
• /
• pp.483-486
• /
• 2008

• Bulletin of the Korean Chemical Society
• /
• 제33권11호
• /
• pp.3640-3644
• /
• 2012

An efficient synthetic method for direct Henry reaction catalyzed by a biguanide; namely metformin, as an organosuper-base, between a variety of aromatic and aliphatic aldehydes and nitromethane under neat conditions has been developed. Convenient procedure for removal of the catalyst, chemoselective acquiring of ${\beta}$-nitroalcohols as predominant products, as far as possible short reaction time with excellent conversions are advantages of the developed protocol.

• Bulletin of the Korean Chemical Society
• /
• 제33권8호
• /
• pp.2546-2552
• /
• 2012

A novel biguanide-functionalized $Fe_3O_4/SiO_2$ magnetite nanoparticle with a core-shell structure was developed for utilization as a heterogeneous organosuperbase in chemical transformations. The structural, surface, and magnetic characteristics of the nanosized catalyst were investigated by various techniques such as transmission electron microscopy (TEM), powder X-ray diffraction (XRD), vibrating sample magnetometry (VSM), elemental analyzer (EA), thermogravimetric analysis (TGA), $N_2$ adsorption-desorption (BET and BJH) and FT-IR. The biguanide-functionalized $Fe_3O_4/SiO_2$ nanoparticles showed a superpara-magnetic property with a saturation magnetization value of 46.7 emu/g, indicating great potential for application in magnetically separation technologies. In application point of view, the prepared catalyst was found to act as an efficient recoverable nanocatalyst in nitroaldol and domino Knoevenagel condensation/Michael addition/cyclization reactions in aqueous media under mild condition. Additionally, the catalyst was reused six times without significant degradation in catalytic activity and performance.