Facile TEMPO Immobilization onto Poly(acrylic acid)-Modified Magnetic Nanoparticles: Preparation and Property

Table 2

TEMPO-MNPs mediated oxidation of alcohols to aldehydes/ketones.

ENTRY	Alcohol	[%]	[%]	[%]
	Benzyl alcohol	99	99	99.0
	4-Chlorobenzyl alcohol	98	98	98.0
	4-Methoxylbenzyl alcohol	99	84.8	85.6
	4-Phenyl-2-butanol	99	95.1	96.1
	Benzyl alcohol	99	96.9	97.8
	4-Chlorobenzyl alcohol	99	83.1	84.0
	4-Methoxylbenzyl alcohol	99	99	99.0

Alcohol (1 mmol) in DCM, potassium bromide solution (1.0 M, 1 mL), 4-methoxyacetophenone (208.0 mg, internal standard), and TEMPO-MNPs (150 mg) were added to a round-bottom flask. The suspension was stirred in ice-water bath before addition of NaClO solution (0.35 M, pH 8.7, 1.05 eq). Sample aliquots were regularly taken and analyzed by GC. A 25 mL Schlenk-flask was charged with a solution of 1 mmol alcohol, TEMPO-MNPs (200 mg), Mn(NO₃)₂ (50%, 120 mg), and Co(NO₃)₂·6H2O (0.4 mmol, 100 mg) and in 15 mL of acetic acid was stirred at 40°C under O₂ at atmospheric pressure. Sample aliquots were regularly taken and analyzed by GC. Conversion, yield, and selectivity were calculated according to GC or GS-MS results in the supporting information.