Silica-ZnCl₂: An Efficient Catalyst for the Synthesis of 4-Methylcoumarins

Table 2

Synthesis of coumarin derivatives using ethyl acetoacetate and substituted phenols in the presence of silica-ZnCl₂.

Entry	Phenol	Product	Time (min)	Yield^a (%)	Melting point (°C)
1			15	95	183-184
2			25	89	130–132
3			20	92	183-184
4			30	90	154-155
5			45	88	221–224
6			45	79	184-185
7			50	80	190-191
8			65	85	243-244

aIsolated yields.