Entry

Catalyst

Conditions

Time (hrs)

Yield (%, w/w)

Reference

1

HY-Zeolite

Ethanol/reflux

2.5 - 3.5

90

31

2

Silica supported sulphuric acid

H₂O/70˚C

1.5

95

32

3

Bronsted acidic ionic liquid

Ethanol/80˚C

1 - 1.5

85

33

4

Methanesulfonic acid

Solvent free/120˚C

1

92

34

5

CuSO₄∙5H₂O

EtOH-H₂O/80˚C

1.5

94

-

6

Ni_0.5Co_0.5Fe₂O₄ NPs

EtOH-H₂O/100˚C

40 min

96

Present work