AuNPs/TiO₂-catalyzed oxidative C–H/C–H homocoupling of aromatic compounds 32.

Entry	R	Au/arene (mol ratio × 100)	TOFa	TONb	Selectivity (%)
1	H	0.022	382	230	99
2	Me	0.026	176	206	98
3	1,5-Me2	0.030	18	71	98
4	1,2,6-Me3	0.034	6	8	98
5	Cl	0.032	368	88	99
6	NO2	0.035	176	175	99
7	OH	0.027	85	336	80

^aTurnover frequency (TOF).

^bTurnover number (TON).