Acetonitrile → Benzaldehyde

The invention relates to a direct method of synthesis of aldehydes and ketones using nano-RuHAP as a general and effective catalyst for the oxidative cleavage of α,β-unsaturated alkenes. To a mixture of CH3CN (7.5 mL) and distilled water (5 mL) containing alkene (104 mg, 0.5 mmol) and nano-RuHAP (40 mg) was added a mixture Oxone (770 mg, 1.25 mmol) and NaHCO3 (330 mg, 2.3 mmol) over a period of 10 min at room temperature. Upon complete reaction based on TLC analysis, excess NaIO4 was quenched by a saturated Na2S2O3 solution. The catalyst was separated from the reaction mixture by centrifugation, and the recovered catalyst was washed with water and dried in vacuum before reuse. The supernatant liquid was extracted with CH2Cl2 (3×10 mL) and the combined organic extracts were dried over anhydrous Na2SO4. The reaction products were purified by flash chromatography and were characterized by IR, MS and NMR spectroscopies. “nano-RuHAP+Oxone” protocol would also effect oxidative cleavage of α,β-unsaturated alkenes. When chalcone (0.5 mmol) was treated with Oxone (1.25 mmol) and nano-RuHAP (4 mol %) in a NaHCO3 buffered MeCN—H2O (1.5:1 v/v) at room temperature for 3 h, benzaldehyde and benzoic acid were produced (entry 1). Similar oxidative cleavage products were found in isophorone and (+)-pulegone (entry 2,3). Notably, facile oxidative cleavage of C≡C bonds was also observed. For example, subjecting alkynes such as 1-phenyl-1-propyne to the Ru-catalyzed conditions produced benzoic acid in 82% yield (entry 4).

1. distillationdistilled water (5 mL)
2. customUpon complete reaction
3. customwas quenched by a saturated Na2S2O3 solution
4. customThe catalyst was separated from the reaction mixture by centrifugation
5. washthe recovered catalyst was washed with water
6. customdried in vacuum before reuse
7. extractionThe supernatant liquid was extracted with CH2Cl2 (3×10 mL)
8. dry with materialthe combined organic extracts were dried over anhydrous Na2SO4
9. customThe reaction products were purified by flash chromatography
10. customat room temperature
11. customfor 3 h

ORD record

ord-f2f671157e554d429ae367bddd047250

Source dataset

uspto-grants-2008_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07393985B2