Table 1.

Bromination of 4 Using NH₄Br and Different Concentrations of PAA in Acetic Acid^a

#	4b (µmol)	NH4Brc (µmol)	PAAd (µmol)	PAA:NH4Br (in µmol)	Reaction Time (min)	Relative Yielde 2 (%)
1	0.17	0.18	39.4	219 : 1	10	(100)
2	0.17	0.18	13.1	73.0 : 1	10	84
3	0.17	0.18	4.4	24.3 : 1	10 25	80 97
4	0.17	0.18	1.5	8.1 : 1	20	94
5	0.17	0.18	0.49	2.7 : 1	20	87
6	0.17	0.18	0.16	0.9 : 1	20	95

^aData from single experiment

^b4 (100 µg, 0.17 µmol) in AcOH (100 µL)

^cA solution of NH₄Br (18 µg, 0.18 µmol) in H₂O (3.0 µL)

^dPAA in AcOH (100 µL)

^eYields are given relative to that obtained in reaction #1, based on HPLC integrations of 2.