We decided to test the effect of different H-TEDA(BF 4 ) 2 additive loadings on this reaction (See the SI file for the details). However, further increasing the H-TEDA(BF 4 ) 2 loading led to lower product yields; e.g., 4.0 eq. and 8.0 eq. of H-TEDA(BF 4 ) 2 provided 63% and 17% product yields respectively (Table and). Next, we tested if the H-TEDA(BF 4 ) 2 additive promotes reactions of other fluorine sources. The standard reaction with SelectFluor II ('SF II' i.e., SF ® where the Cl atom is replaced by H) instead of SF ® provided only 36% of 2a (Table ). However, the same reaction with addition of 2.0 eq. H-TEDA(BF 4 ) 2 gave 64% of 2a ). The standard reaction with N-fluorobenzenesulfonimide (NFSI) instead of SF ® did not afford 2a (Table ). However, the same reaction with addition of 2.0 eq. H-TEDA(BF 4 ) 2 provided 27% of 2a (Table ). Thus, the promotionary effect of H-TEDA(BF 4 ) 2 is not limited to SF ® and is general to other fluorine sources.