Ultrasound-assisted synthesis of 2,4-thiazolidinedione and rhodanine derivatives catalyzed by task-specific ionic liquid: [TMG][Lac]

Organic and Medicinal Chemistry Letters

Table 3 [TMG][Lac]-catalyzed solvent-free reactions of thiazolidines 3 with aldehydes 2

Entry	Aldehydes	Thiazolidenes	Product ^a	Time (min)	Yield (%) ^b
1	2a	3a	4a	20	95
2	2b	3a	4b	15	98
3	2c	3a	4c	25	91
4	2d	3a	4d	30	92
5	2e	3a	4e	20	96
6	2a	3b	5a	15	97
7	2b	3b	5b	10	99
8	2c	3b	5c	20	92
9	2d	3b	5d	25	91
10	2e	3b	5e	15	98

^aReaction conditions: 2a-2e (1 mmol), 3a-3b (1 mmol), and 1c (20 mol%) were irradiated under ultrasound irradiations at 80°C. The products were characterized by spectral techniques like IR, ¹H NMR, ¹³C NMR, and mass spectra. ^bIsolated yields after recrystallization.

Entry	Aldehydes	Thiazolidenes	Product ^a	Time (min)	Yield (%) ^b
1	2a	3a	4a	20	95
2	2b	3a	4b	15	98
3	2c	3a	4c	25	91
4	2d	3a	4d	30	92
5	2e	3a	4e	20	96
6	2a	3b	5a	15	97
7	2b	3b	5b	10	99
8	2c	3b	5c	20	92
9	2d	3b	5d	25	91
10	2e	3b	5e	15	98

Entry	Aldehydes	Thiazolidenes	Product ^a	Time (min)	Yield (%) ^b
1	2a	3a	4a	20	95
2	2b	3a	4b	15	98
3	2c	3a	4c	25	91
4	2d	3a	4d	30	92
5	2e	3a	4e	20	96
6	2a	3b	5a	15	97
7	2b	3b	5b	10	99
8	2c	3b	5c	20	92
9	2d	3b	5d	25	91
10	2e	3b	5e	15	98

Entry	Aldehydes	Thiazolidenes	Product ^a	Time (min)	Yield (%) ^b
1	2a	3a	4a	20	95
2	2b	3a	4b	15	98
3	2c	3a	4c	25	91
4	2d	3a	4d	30	92
5	2e	3a	4e	20	96
6	2a	3b	5a	15	97
7	2b	3b	5b	10	99
8	2c	3b	5c	20	92
9	2d	3b	5d	25	91
10	2e	3b	5e	15	98