Entry

Catalyst

Solvent

Yield (%)^b

1

none

EtOH

0

2

NH₄Cl

EtOH

95

3

NH₄Cl

CH₂Cl₂

0

4

NH₄Cl

ether

<20

5

NH₄Cl

toluene

<20

6

NaCl

EtOH

0

7

[BMIM]^{+ ${\text{BF}}_4^{+}$}

EtOH

0