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Efficient Metal-Free Aerobic Photooxidation of Sulfides to Sulfoxides
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to the general procedure using 1 (22 mg, 0.04 mmol). Crude
material was purified by column chromatography (dichloro-
0.9 Hz, 2H); C NMR (101 MHz, chloroform-d): d=143.04,
131.22, 129.16, 125.36, 124.46, 60.99.
methane-ethyl acetate=3:1) to give 3d; yield: 300 mg
Benzyl phenyl sulfoxide (3k): Benzyl phenyl sulfide (2k)
(401 mg, 2 mmol) was treated according to the general pro-
cedure using 1 (22 mg, 0.04 mmol). Crude material was puri-
fied by column chromatography (dichloromethane-ethyl
1
(
2
86%). H NMR (400 MHz, chloroform-d): d=7.62–7.56 (m,
H), 7.54–7.48 (m, 2H), 2.71 (s, 3H); C NMR (101 MHz,
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chloroform-d): d=144.38, 137.39, 129.79, 125.10, 44.20.
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4-Bromophenyl methyl sulfoxide (3e): 4-Bromophenyl
acetate=4:1) to give 3k; yield: 398 mg (92%). H NMR
methyl sulfide (2e) (406 mg, 2 mmol) was treated according
to the general procedure using 1 (22 mg, 0.04 mmol). Crude
material was purified by column chromatography (dichloro-
(300 MHz, chloroform-d): d=7.51–6.93 (m, 10H), 4.15–3.93
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3
(m, 2H); C NMR (101 MHz, chloroform-d): d=142.86,
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31.27, 130.46, 129.23, 128.95, 128.56, 128.35, 124.54, 63.69.
Diphenyl sulfoxide (3l): Diphenyl sulfide (2l) (373 mg,
mmol) was treated according to the general procedure
methane-ethyl acetate=3:1) to give 3e ; yield: 381 mg
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2
(
2
87%). H NMR (400 MHz, chloroform-d): d=7.70–7.64 (m,
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using 1 (22 mg, 0.04 mmol). Crude material was purified by
H), 7.56–7.49 (m, 2H), 2.72 (s, 3H); C NMR (101 MHz,
column chromatography (hexan-ethyl acetate=2:1) to give
chloroform-d): d=145.00, 132.72, 125.62, 125.28, 44.15.
Methyl 4-nitrophenyl sulfoxide (3f): Methyl 4-nitrophenyl
sulfide (2f) (338 mg, 2 mmol) was treated according to the
general procedure using 1 (22 mg, 0.04 mmol). Crude mate-
rial was purified by column chromatography (dichlorome-
thane-ethyl acetate=2:1) to give 3f; yield: 300 mg (81%).
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3
l; yield: 324 mg (80%). H NMR (400 MHz, chloroform-d):
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d=7.68–7.61 (m, 2H), 7.49–7.41 (m, 3H);
C NMR
(
101 MHz, chloroform-d): d=145.70, 131.18, 129.44, 124.90;
+
+
HR-MS (ESI ): m/z=203.05261, calcd. for C H OS [M+
H] : 203.05251.
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+
1
Benzyl methyl sulfoxide (3m): Benzyl methyl sulfide (2m)
(276 mg, 2 mmol) was treated according to the general pro-
cedure using 1 (22 mg, 0.04 mmol). Crude material was puri-
fied by column chromatography (dichloromethane-ethyl
H NMR (400 MHz, chloroform-d): d=8.40 (d, J=8.6 Hz,
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2
H), 7.87–7.80 (m, 2H), 2.80 (s, 3H); C NMR (101 MHz,
chloroform-d): d=153.38, 149.61, 124.77, 124.60, 44.00.
-Chlorophenyl methyl sulfoxide (3g): 2-Chlorophenyl
2
1
acetate=5:1) to give 3m; yield: 274 mg (89%). H NMR
methyl sulfide (2g) (317 mg, 2 mmol) was treated according
to the general procedure using 1 (22 mg, 0.04 mmol). Crude
material was purified by column chromatography (dichloro-
(400 MHz, chloroform-d): d=7.42–7.27 (m, 5H), 4.06 (d, J=
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2.6 Hz, 1H), 3.92 (d, J=12.5 Hz, 1H), 2.45 (s, 3H);
C NMR (101 MHz, chloroform-d): d=130.14, 129.75,
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methane-ethyl acetate=4:1) to give 3g; yield: 311 mg
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128.58, 128.49, 60.44, 37.40.
(
89%). H NMR (500 MHz, chloroform-d): d=7.96 (dd, J=
Dibutyl sulfoxide (3n): Dibutyl sulfide (2n) (293 mg,
2 mmol) was treated according to the general procedure
using 1 (22 mg, 0.04 mmol). Crude material was purified by
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1
.8, 1.4 Hz, 1H), 7.57–7.51 (m, 1H), 7.45 (td, J=7.6, 1.5 Hz,
H), 7.39 (dd, J=7.9, 1.0 Hz, 1H), 2.82 (s, 3H); C NMR
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(
1
126 MHz, chloroform-d): d=143.78, 132.13, 129.90, 128.30,
column chromatography (dichloromethane-ethyl acetate=
+
25.47, 125.12, 41.81; HR-MS (ESI ): m/z=196.98002, calcd.
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5
:1) to give 3n; yield: 282 mg (87%). H NMR (400 MHz,
+
+
for C H OClSNa [M+Na] : 196.97983.
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chloroform-d): d=2.77–2.56 (m, 2H), 1.84–1.69 (m, 2H),
2-Bromophenyl methyl sulfoxide (3h): 2-Bromophenyl
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1
.57–1.37 (m, 2H), 0.96 (t, J=7.3 Hz, 3H); C NMR
methyl sulfide (2h) (406 mg, 2 mmol) was treated according
to the general procedure using 1 (22 mg, 0.04 mmol). Crude
material was purified by column chromatography (dichloro-
(101 MHz, chloroform-d): d=52.34, 24.76, 22.24, 13.84.
Modafinil (3o): Deoxy-modafinil (2o) (515 mg, 2 mmol)
was treated according to the general procedure using
(22 mg, 0.04 mmol). Crude material was purified by
methane-ethyl acetate=4:1) to give 3h; yield: 390 mg
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1
(
89%). H NMR (400 MHz, chloroform-d): d=7.98–7.92 (m,
column chromatography (dichloromethane-methanol=10:1)
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H), 7.62–7.54 (m, 2H), 7.38 (ddd, J=8.0, 7.3, 1.7 Hz, 1H),
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to give 3o; yield: 492 mg (90%). H NMR (300 MHz, chloro-
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.84 (s, 3H); C NMR (101 MHz, chloroform-d): d=145.10,
form-d): d=7.54–7.30 (m, 10H), 5.57 (s, 2H), 3.49 (d, J=
+
33.10, 132.51, 128.93, 125.90, 118.59, 41.90; HR-MS (ESI ):
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1
4.5 Hz, 1H), 3.10 (dd, J=14.5, 1.0 Hz, 1H); C NMR
+
m/z=240.9296, 242.9272, calcd. for C H OBrSNa [M+Na] :
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(101 MHz, chloroform-d): d=166.21, 134.37, 134.18, 129.66,
79
81
2
40.9293 (for Br), 242.9273 (for Br).
tert-Butyl phenyl sulfoxide (3i): tert-Butyl phenyl sulfide
2i) (333 mg, 2 mmol) was treated according to the general
129.48, 129.12, 129.09, 128.95, 128.86, 71.80, 51.28.
N-Acetyl l-methionine sulfoxide (3p): N-Acetyl l-methio-
(
nine (2p) (382 mg, 2 mmol) was treated according to the
general procedure using 1 (22 mg, 0.04 mmol). Crude mate-
rial was purified by reverse phase flash chromatography
procedure using 1 (22 mg, 0.04 mmol). Crude material was
purified by column chromatography (dichloromethane-ethyl
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acetate=3:1) to give 3i; yield: 288 mg (79%). H NMR
(
3
gradient 5% methanol in water to pure methanol) to give
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(
500 MHz, chloroform-d): d=7.61–7.56 (m, 2H), 7.49 (dd,
p; yield: 332 mg (80%). H NMR (400 MHz, methanol-d ):
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J=5.1, 1.7 Hz, 3H), 1.17 (s, 9H); C NMR (126 MHz,
chloroform-d): d=140.17, 131.25, 128.51 (d, J=4.5 Hz),
d=4.54 (td, J=7.8, 5.0 Hz, 1H), 3.01–2.75 (m, 2H), 2.66 (d,
J=0.7 Hz, 3H), 2.39–2.29 (m, 1H), 2.11 (s, 1H), 2.01 (d, J=
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126.44, 55.90, 22.93.
1.0 Hz, 3H); C NMR (151 MHz, methanol-d ): d=174.12,
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Allyl phenyl sulfoxide (3j): Allyl phenyl sulfide (2j)
173.43 (d, J=10.0 Hz), 52.78, 52.52, 51.20, 38.17 (d, J=
À
(300 mg, 2 mmol) was treated according to the general pro-
12.0 Hz), 25.95; HR-MS (ESI ): m/z=206.04897, calcd. for
À
+
cedure using 1 (22 mg, 0.04 mmol). Crude material was puri-
C H NO S [MÀH] : 206.04925; HR-MS (ESI ): m/z=
7
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4
+
fied by column chromatography (dichloromethane-ethyl
230.04580, calcd. for C H NO SNa [M+Na] : 230.04575.
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1
acetate=5:1) to give 3j; yield: 279 mg (84%). H NMR
2-Chloroethyl ethyl sulfoxide (3r): (2-Chloroethyl)-ethyl-
sulfide (2r) (249 mg, 2 mmol) was treated according to the
general procedure using 1 (22 mg, 0.04 mmol). Crude mate-
rial was purified by reverse phase flash chromatography
(400 MHz, chloroform-d): d=7.63–7.57 (m, 2H), 7.54–7.45
(m, 3H), 5.72–5.56 (m, 1H), 5.32 (ddd, J=10.2, 1.4, 0.8 Hz,
1
H), 5.19 (dq, J=17.1, 1.3 Hz, 1H), 3.53 (qdt, J=12.9, 7.5,
Adv. Synth. Catal. 2016, 358, 1654 – 1663
ꢀ 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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