Molybdenum Hexacarbonyl and DBU Reduction of Nitro Compounds under Microwave Irradiation

Abstract

An ethanolic mixture of molybdenum hexacarbonyl and DBU mediates the reduction of nitroarenes to the corresponding anilines in excellent yields in 15-30 minutes under microwave ­irradiation.

Key words

amines - microwave - molybdenum - nitroarenes - reductions

References and Notes

• Reviews:
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  Typical Work-up
  After solvent concentration, the resulting crude product is passed over a short SiO₂ plug (6 cm × 3 cm). Typical eluent: neat CH₂Cl₂ to 5:1 CH₂Cl₂-acetone gradient. All products were characterised by ¹H NMR, ¹³C NMR, GC-MS, or MS and correspond to commercial samples or literature values (see ref. 7b and also ref. 9). Compound 2o: ¹H NMR (270 MHz): δ = 3.67 (2 H, br s), 4.67 (2 H, s), 6.54 (1 H, d, J = 8.4 Hz), 6.78 (1 H,s), 7.07 (1 H, s), 7.11 (1 H, s). ¹³C NMR (67 MHz): δ = 62.9, 115.1, 121.1, 129.8, 138.7, 145.4.

• 7b The Aldrich Library of ¹³C and ¹H FT NMR Spectra   1st ed.:  Pouchert CJ. Behnke J. Aldrich Chemical Company; USA: 1993. 
• Similar ‘multifunctional’ nitro analogues were selectively reduced with H₂ in the presence of catalytic gold nanoparticles:
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• For example; kinase inhibitors:
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8

Spencer, J.; Rathnam, R. P.; Patel, H.; Anjum, N., manuscript in preparation.