Table 2. Conditions Screening of the Cu(BF₄)₂/AC-Catalyzed Oxidative Coupling Reaction of Phenylamine with ortho-Tolylboronic Acid^a.

entry	oxidantb	additivec	solventd	yield (%)
1	air	K2CO3	1,4-dioxane	38
2	O2	K2CO3	1,4-dioxane	41
3	DTBP	no base	1,4-dioxane	57
4	DTBP	M.s. 3 Å	1,4-dioxane	58
5	DTBP	M.s. 3 Å	methanol	93

^aUnless otherwise noted, all of the reactions were run with 1a (1.0 mmol), 2b (2.5 mmol).

^bReaction performed using DTBP (2.0 mmol), O₂ balloon, air = open flask.

^cK₂CO₃ (2.0 mmol).

^d1,4-Dioxane (10.0 mL), methanol (2.0 mL).