MCM-41-Accelerated PWA Catalysis of Friedel-Crafts Reaction of Indoles and Isatins

Table 2

Substrate scope for the cyclocondensation .

Entry	R^1	R^2	Products	Yield	Yield	Ref.
(1)	H	H	3a	99	89	[10]
(2)	2-CH3	H	3b	70	91	[9]
(3)	5-CH3	H	3c	55	85	[14]
(4)	6-CH3	H	3d	80	86	[14]
(5)	5-F	H	3e	96	87	[10]
(6)	6-F	H	3f	98	-	-
(7)	5-Cl	H	3g	98	89	[26]
(8)	6-Cl	H	3h	98	91	[26]
(9)	5-NO2	H	3i	72	84	[14]
(10)	6-NO2	H	3j	64	-	-
(11)	H	1-CH3	3k	76	91	[10]
(12)	H	5-CH3	3l	98	90	[9]
(13)	H	5-Cl	3m	99	86	[10]
(14)	H	4-Br	3n	60	90	[14]
(15)	H	7-F	3o	99	-	-

conditions (unless noted otherwise): indoles (1, 0.20 mmol), isatins (2, 0.10 mmol), and 0.0050 g 60 wt% PWA/MCM-41 as catalyst in 0.3 mL THF at room temperature for 2.5 h. yield. of reference.