Synthesis of β-Nitroamines Using Nanocrystalline MgO

Abstract

Nanocrystalline magnesium oxide (NAP-MgO) was found to be an effective heterogeneous, solid base catalyst for the direct aza-Henry reaction of nitroalkanes and various N-arylidene-4-methylbenzenesulfonamides to afford the corresponding β-nitroamines in excellent yields under mild conditions. The catalyst was recovered by simple centrifugation and reused for three cycles with consistent activity.

Keywords:

• Aza-Henry reaction
• heterogeneous
• NAP-MgO
• β-nitroamines
• solid base

ACKNOWLEDGMENTS

We thank the Council of Scientific and Industrial Research (CSIR) for financial support under the Task Force Project CMM-0005. L. C. P. thanks the CSIR, India, for providing a senior research fellowship.

Notes

^a Conditions: catalyst (10 mg), N-(4-chlorobenzylidene)-4-methylbenzene-sulfonamide (0.25 mmol), nitromethane (10 equiv.).

^b Isolated yields.

^a Conditions: NAP-MgO (10 mg), N-(4-chlorobenzylidene)-4-methyl-benzenesulfonamide (0.25 mmol), nitromethane (10 equiv.), solvent (2 mL).

^b Isolated yield.

^a Conditions: Catalyst (10 mg), N-arylidene-4-methylbenzene sulfonamide (0.25 mmol), nitroalkane (10 equiv.), DMF (2 mL).

^b Isolated yields.

^c Yield after third cycle.