Hantzsch Reaction Starting Directly from Alcohols through a Tandem Oxidation Process

Table 2

Hantzsch reaction of different substrates catalyzed by [DDPA][HSO₄].

Entry	R^1	R^2	Time (h)	Yield (%)	Mp °C (lit. Mp °C)
1	C6H5	CH3	1	91	118 (118) [7]
2	4-MeO-C6H4	CH3	1	93	91 (92) [7]
3	4-Cl-C6H4	CH3	2	85	118 (120) [7]
4	C6H5	CH3CH2	1	90	60-61 (63-64) [23]
5	2-MeO-C6H4	CH3CH2	1	93	58 (55–57) [24]
6	4-MeO-C6H4	CH3CH2	1	91	52 (51-52) [7]
7	4-Cl-C6H4	CH3CH2	2	83	66 (65–67) [23]
8	3-NO2-C6H4	CH3CH2	3	76	60 (60) [7]
9	4-NO2-C6H4	CH3CH2	3	72	115 (114-115) [23]

Benzyl alcohol (3 mmol), ethyl acetoacetate (3 mmol), ammonium acetate (3 mmol), ionic liquid (1.2 mmol), and NaNO₃ (6 mmol). Yields were based on GC analysis and referred to the desired product 3. Mp of product 3.