Table 1. Screening of Iodination Conditions^a.

entry	Pd (II)b	basec	solventd	yield (%)e
1	Pd(OAc)2	–	DMF	15
2	Pd(OAc)2	CsOAc	DMF	62
3	Pd(OAc)2	CsOAc	t-AmylOH	<5
4	Pd(OAc)2	CsOAc	DMF/t-AmylOH	80
5	Pd(OAc)2	CsOAc/NaHCO3f	DMF/t-AmylOH	99
6	Pd(OAc)2	NaHCO3f	DMF/t-AmylOH	35
7g	Pd(OAc)2	CsOAc/NaHCO3f	DMF/t-AmylOH	98 (95%h)
8	–	CsOAc/NaHCO3f	DMF/t-AmylOH	0
9	PdCl2	CsOAc/NaHCO3f	DMF/t-AmylOH	83
10	PdI2	CsOAc/NaHCO3f	DMF/t-AmylOH	75
11	PdI2	–	DMF/t-AmylOH	<5

^aThe reactions were run on 0.10 mmol scale in a 25 mL-sealed tube under aira.

^b5 mol % of the Pd(II) catalyst was used unless otherwise stated.

^c1.2 eq of CsOAc was used.

^dSolvent volume = 2.0 mL; DMF/t-AmylOH = 1:1.

^e% yield was determined e by the 1H NMR spectroscopy using CH₂Br₂ as the internal standard.

^f1.0 eq of NaHCO₃ was added.

^gThe reaction was run on 0.30 mmol scale with 2 mol % Pd(OAc)₂ in 5.0 mL of solvent.

^hYield of the isolated product.