La_𝟐O_𝟑 Catalyzed C–C Coupling of Aryl Iodides and Boronic Acids

Table 1

La₂O₃-catalyzed C–C coupling of aryl halides with phenyl boronic acid.

Entry	Base	Ligand	Catalyst	Solvent	Time (h)^a	Yield (%)^b
1	NaOH	L2	La2O3	DMSO	18	65
2	Na2CO3	L2	La2O3	DMSO	16	23
3	KO-t-Bu	L2	La2O3	DMSO	17	84
4	Cs2CO3	L2	La2O3	DMSO	18	70
5	K2CO3	L2	La2O3	DMSO	16	72
6	KOH	L2	La2O3	DMSO	15	70
7	KO-t-Bu	L2	La2O3	DMF	18	73
8	KO-t-Bu	L2	La2O3	THF^c	19	15
9	KO-t-Bu	L2	La2O3	Toluene^c	21	40
10	KO-t-Bu	L2	La2O3	CH3NO2^c	23	22
11	KO-t-Bu	L2	La2O3	CH3CN^c	23	51
12	KO-t-Bu	L2	La2O3	EtOAc^c	24	10
13	KO-t-Bu	L2	La2O3	1,4-dioxane^c	24	15
14	KO-t-Bu	L1	La2O3	DMSO	21	32
15	KO-t-Bu	L3	La2O3	DMSO	24	73
16	KO-t-Bu	L4	La2O3	DMSO	20	80
17	KO-t-Bu	L5	La2O3	DMSO	25	20
18	KO-t-Bu	L6	La2O3	DMSO	20	51

^aMonitored using TLC. ^bIsolated yield after column chromatography of the crude product. ^cThe reaction mixture was set to reflux.