Table 3. Synthesis of 2-Arylidenindane-1,3-diones Promoted by 2-HEAF.

entry	aldehyde	yield %	mp (°C)
1	R1, R2, R3 = H	98	150
2	R1, R2 = H; R3 = CH3	98	150–152
3	R1, R2 = H; R3 = OCH3	98	159
4	R1, R2 = H; R3 = NO2	98	230–232
5	R1 = OCH3; R2, R3 = H	85	168
6	R1, R2 = OCH3; R3 = H	98	159
7	R1, R3 = OCH3; R2 = H	98	204
8	R1, R3 = H; R2 = NO2	98	251–252
9	R1, R2 = H; R3 = Cl	98	178
10	R1, R3 = Cl; R2 = H	88	194
11	4-(dimethylamino)-benzaldehyde	98	205
12	5-methyl-2-furaldehyde	98	169–170
13	2-thiophencarboxaldehyde	98	176–178
14	1-naphthaldehyde	98	175
15	biphenyl-4-carbaldehyde	90	238–240
16	4-(dimethylamino)-cinnammaldehyde	98	252–253
17	4-(12-bromododecyloxy) benzaldehyde	60	104–106