Comparison of the synthesis of 6d with the previously reported procedure.

Entry	Conditions	Time/yield (%)	Ref.
1	CH2Cl2/rt	24 h/48	60
2	Fe3−xBixO4/SiO2@l-ArgEt3+I−/Zn(ii) (0.012 g)/EtOH (3 mL)/rt	9 h/83	This work
3	Fe3−xBixO4/SiO2@l-ArgEt3+I−/Zn(ii) (0.012 g)/EtOH (3 mL)/rt/Us	60 min/71	This work