SPECIAL TOPIC
Aerobic Photooxidation
2687
OO•
OH
AQN*
AQH• AQN
AQH•
•
O2
OH
OH
1
5
4
6
8
OOH
O
OH
OH
AQH•
AQN*
H2O
OH
H
H2O2
7
9
OH
HO
OO•
HO
OOH
OH
AQH• AQN
•
O2
OH
OH
H2O
10
11
O
O
H2O H2O2
acid or base
OH
OOH
2
3
Scheme 6 Plausible path for the aerobic photooxidation
1H NMR (500 MHz, CDCl3): δ = 8.13 (d, J = 7.4 Hz, 2 H), 7.62 (t,
J = 7.4 Hz, 1 H), 7.48 (t, J = 7.4 Hz, 2 H).
p-Bromobenzoic Acid (2e)
CAS Registry Number: 586-76-5
13C NMR (125 MHz, acetone-d6): δ = 172.6, 133.9, 130.3, 129.4,
128.6.
Yield: Method A, 51.9 mg (87%); Method B, 50.1 mg (83%); col-
orless solid; mp 250–252 °C.
1H NMR (500 MHz, acetone-d6): δ = 7.93 (d, J = 8.6 Hz, 2 H), 7.67
(d, J = 8.6 Hz, 2 H).
13C NMR (100 MHz, acetone-d6): δ = 166.9, 132.6, 132.3, 130.7,
MS: m/z = 122 (M+), 105, 77.
The synthesized compounds 2a–e have been reported in the litera-
ture and were characterized by comparing the corresponding spec-
troscopic data.4 The products 2f–k were identified by comparison of
their analytical data with those of authentic samples.
128.1.
MS: m/z = 200 (M+), 183, 155.
1-Dodecanoic Acid (2g)
4-tert-Butylbenzoic Acid (2b)
CAS Registry Number: 98-73-7
CAS Registry Number: 143-07-7
Yield: Method A, 46.4 mg (87%); Method B, 48.2 mg (90%); col-
orless solid; mp 163–164 °C.
1H NMR (500 MHz, CDCl3): δ = 8.06 (d, J = 8.7 Hz, 2 H), 7.49 (d,
J = 8.7 Hz, 2 H), 1.35 (s, 9 H).
13C NMR (125 MHz, CDCl3): δ = 172.6, 157.7, 130.2, 126.7, 125.6,
35.3, 31.2.
Yield: Method A, 21.4 mg (36%); Method B, 19.5 mg (32%); col-
orless solid; mp 43–44 °C.
1H NMR (500 MHz, CDCl3): δ = 2.35 (t, J = 7.4 Hz, 2 H), 1.66–1.60
(m, 2 H), 1.35–1.26 (m, 16 H), 0.88 (t, J = 6.9 Hz, 3 H).
13C NMR (125 MHz, CDCl3): δ = 180.2, 34.2, 32.0, 29.7, 29.5, 29.4,
29.3, 29.1, 24.8, 22.8, 14.2.
MS: m/z = 178 (M+), 163, 135, 91.
MS: m/z = 200 (M+), 129, 73.
p-Methoxybenzoic Acid (2c)
CAS Registry Number: 100-09-4
Acetophenone (2h)
CAS Registry Number: 98-86-2
Yield: Method A, 37.6 mg (82%); Method B, 39.7 mg (87%); col-
orless solid; mp 181–183 °C.
1H NMR (400 MHz, acetone-d6): δ = 7.96 (d, J = 9.2 Hz, 2 H), 7.0
(d, J = 9.2 Hz, 2 H), 3.85 (s, 3 H).
13C NMR (100 MHz, acetone-d6): δ = 167.5, 164.4, 132.5, 123.7,
114.5, 55.8.
Yield: 27.5 mg (76%); colorless oil.
1H NMR (500 MHz, CDCl3): δ = 7.96 (d, J = 8.0 Hz, 2 H), 7.57 (t,
J = 8.0 Hz, 1 H), 7.47 (t, J = 8.0 Hz, 2 H), 2.61 (s, 3 H).
13C NMR (125 MHz, CDCl3): δ = 198.3, 137.2, 133.2, 128.7, 128.4,
26.7.
MS: m/z = 120 (M+), 105, 77.
MS: m/z = 152 (M+), 135, 107.
Indanone (2i)
p-Chlorobenzoic Acid (2d)
CAS Registry Number: 83-33-0
CAS Registry Number: 74-11-3
Yield: 31.0 mg (78%); colorless solid; mp 38–40 °C.
Yield: Method A, 42.6 mg (91%); Method B, 39.7 mg (85%); col-
orless solid; mp 236–237 °C.
1H NMR (500 MHz, acetone-d6): δ = 8.01 (d, J = 8.6 Hz, 2 H), 7.53
(d, J = 8.6 Hz, 2 H).
13C NMR (100 MHz, acetone-d6): δ = 166.7, 139.5, 132.1, 130.3,
129.5.
1H NMR (500 MHz, CDCl3): δ = 7.77 (d, J = 8.1 Hz, 1 H), 7.61–
7.57 (m, 1 H), 7.48 (d, J = 8.0 Hz, 1 H), 7.39–7.36 (m, 1 H), 3.16–
3.14 (m, 2 H), 2.71–2.68 (m, 2 H).
13C NMR (125 MHz, CDCl3): δ = 207.2, 155.3, 137.2, 134.7, 127.4,
126.8, 123.8, 36.3, 25.9.
MS: m/z = 132 (M+), 104, 78.
MS: m/z = 156 (M+), 139, 111.
© Georg Thieme Verlag Stuttgart · New York
Synthesis 2013, 45, 2684–2688