Table 3.

Pd-catalyzed and NO_x-mediated aerobic acetoxylation of benzene: Optimization of turnover numbers.

Entrya	% NOx	TON (Pd)b	PhOAc:PhNO2c
1	30% t-BuONO	4	4:1
2	30% NaNO3	59	9:1
3	30% aq. HNO3 (70%)	115	25:1
4d	30% fuming HNO3	136	26:1
5	10% fuming HNO3	100	29:1
6	50% fuming HNO3	127	22:1
7	70% fuming HNO3	116	18:1
8	30% fuming HNO3; N2 (1 atm) instead of O2	19	1:1.2
9e	30% fuming HNO3, 85 °C, air (1 atm) instead of O2	120	40:1

^a1.2 mmol scale; 0.55 M. Reactions were conducted in sealed pressure tubes with teflon caps. Biphenyl is not observed.

^bTONs were calculated based on calibrated GC yields of PhOAc.

^cBased on the ratio of calibrated GC yields.

^dAverage of four experiments. Standard deviation for TON: 9.9. Standard deviation for ratio of PhOAc:PhNO₂: 3.3

^e13.56 mmol scale; 0.55 M. Reaction was conducted in a flask equipped with a reflux condenser. Biphenyl is not observed.