Table 1.

Optimizing the reaction conditions^a.

entry	catalyst 5 mol %	phosphine 10 mol %	base	solvent	time [h]	temp [°C]	yield [%]b
1c	Pd2dba3	SPhos	NaOt-Bu	toluene	19	105	traced
2c	Pd2dba3	SPhos	Cs2CO3	toluene	19	105	traced
3	Pd2dba3	SPhos	Cs2CO3	toluene	5	105	35
4	Pd2dba3	P(t-Bu)3	Cs2CO3	toluene	4	105	34
5	Pd2dba3	dppf	Cs2CO3	toluene	13	105	14
6	Pd2dba3	Xantphos	Cs2CO3	toluene	14	105	46
7	Pd2dba3	BINAP	Cs2CO3	p-xylene	16	125	16
8	Pd2dba3	t-Bu-Xantphos	Cs2CO3	p-xylene	16	125	traced
9	Pd2dba3	DPE-Phos	Cs2CO3	p-xylene	14	125	34
10	Pd2dba3	Xantphos	Cs2CO3	p-xylene	12	125	42
11	Pd2dba3	Xantphos	Cs2CO3	DME	13	79	39
12	Pd(OAc)2	Xantphos	Cs2CO3	p-xylene	2.5	125	45e
13	Pd(OAc)2	Xantphos	Cs2CO3	DME	3	79	12
14	Pd(OAc)2	Xantphos	NaOt-Bu	p-xylene	3	125	traced
15f	Pd(OAc)2	Xantphos	Cs2CO3	p-xylene	4	126	51

^aAll reactions were run using iodonium salt 1 (0.35 mmol), 1.2 equiv of aniline 2a, 2.7 equiv of base, and 5 mL of solvent. ^bIsolated yield after column chromatography. ^c2 mol % Pd₂dba₃ and 4 mol % SPhos were used. ^dProduct not isolated. ^e1.0 equiv of aniline 2a was used. ^f10 mol % Pd(OAc)₂ and 20 mol % Xantphos were used. Pd₂dba₃ = tris(dibenzylideneacetone)dipalladium(0), SPhos = 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl, dppf = 1,1'-bis(diphenylphosphino)ferrocene, Xantphos = 9,9-dimethyl-4,5-bis(diphenylphosphino)xanthene, BINAP = 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl, t-Bu-Xantphos = 4,5-bis(di-tert-butylphosphino)-9,9-dimethylxanthene, DPEphos = bis[(2-diphenylphosphino)phenyl] ether.