In the reaction
the electrophile involved is:
1
Dichloromethyl cation \(\left( {\mathop C\limits^ \oplus HC{I_2}} \right)\)
2
Formyl cation \(\left( {\mathop C\limits^ \oplus HO{}} \right)\)
3
Dichlorocarbene \(\left( {:\mathop C\limits CI_2{}} \right)\)
4
Dichloromethyl anion \(\left( {\mathop C\limits^ \oplus HC{I_2}} \right)\)