Cellulose-Sulfuric Acid as an Efficient Biosupported Catalyst in One-Pot Synthesis of Novel Heteroaryl Substituted 1,4-Dihydropyridines

Table 1

Synthesis of heteroaryl substituted 1,4-dihydropyridines in the presence of cellulose-sulfuric acid catalyst.

Entry^a	Ar	2	Time (min)	Product	Yield (%)^b
a	Ph	Dimedone	42 (120)^c	5a	90 (75)^c
b	𝑝-NO2C6H4	Dimedone	45	5b	95
c	𝑝-ClC6H4	Dimedone	40	5c	94
d	Ph	1,3-Cyclohexanedione	43 (125)^c	5d	88 (72)^c
e	𝑝-NO2C6H4	1,3-Cyclohexanedione	45	5e	87
f	𝑝-ClC6H4	1,3-Cyclohexanedione	42	5f	86
g	Ph	1,3-Indanedione	39 (120)^c	5g	90 (75)^c
h	𝑝-NO2C6H4	1,3-Indanedione	41	5h	86
i	𝑝-ClC6H4	1,3-Indanedione	37	5i	85

aAll products were characterized by ¹H NMR, ¹³C NMR, and IR data.
^bIsolated yields.
^cMeasured in the absence of the catalyst.