Solvent-Free Henry and Michael Reactions with Nitroalkanes Promoted by Potassium Carbonate as a Versatile Heterogeneous Catalyst

Table 2

Optimization of Michael reaction using model reaction.

Entry	Mol %; catalyst	Time; (h)	Temperature; (°C)	Yield of 6; (%)
1	10	5	25	47
2	10	27	25, 60	50
3	20	24	25	58
4	10	7	60	54
5	30	7.5	25	60
6	30	48	25	61
7	30	6	50	58
8	30	7	35	55

Yield of pure isolated product.
Reaction was carried out at room temperature for 24 hours; temperature was increased to 60°C for 3 hours.