The Journal of Organic Chemistry
NOTE
photosensitizer (0.1 mM) was irradiated with a 500-W halogen lamp
under aerobic conditions (in an open flask with vigorous stirring) for 1 h.
An ice bath was used to maintain the reaction temperature around 0 °C
8.47 ppm (m, 2H); 13C NMR (CDCl3) δ 119.6, 121.1, 137.3, 149.5,
158.9 ppm.
Bis(2-benzothiazolyl) disulfide:7f colorless solids, mp 178ꢀ179 °C
(lit.7f mp 177ꢀ179 °C); 1H NMR (CDCl3) δ 7.36 (ddd, J = 8, 7, and 1 Hz,
2H), 7.47 (ddd, J = 8, 7, and 1 Hz, 2H), 7.77 (d, J = 8 Hz, 2H), 7.94 ppm
(d, J = 8 Hz, 4H); 13C NMR (CDCl3) δ 121.3, 122.7, 125.3, 126.6, 136.1,
154.5, 167.9 ppm.
1
during irradiation. The progress of the reaction was monitored by H
NMR spectroscopy, and T50 of the starting thiol was determined by
integration of the 1H NMR signals with use of an appropriate internal
standard. After the solvent was evaporated, the residue was analyzed by
1H NMR spectroscopy to determine the final conversion. The disulfide
product was isolated by using flash column chromatography on silica gel,
and the yields are compiled in Tables 1, 2, and 3. Identification of the
products was carried out by comparison of physical and spectral (1H and
13C NMR) data to those reported in the literature.
N,N0-Diacetyl-L-cystine:32,33 amorphous solids; [R]24D ꢀ102.95
(c 1.06, D2O) [lit.33 [R]24D ꢀ106.51 (c 1.12, D2O)]; 1H NMR (D2O)
δ 2.04 (s, 6H), 3.02 (dd, J = 14 and 9 Hz, 2H), 3.15 (dd, J = 14 and 4 Hz,
2H), 4.71 ppm (dd, J = 9 and 4 Hz, 2H); 13C NMR (D2O) δ 22.1, 39.0,
52.2, 174.2, 174.6 ppm.
L-Cystine:34,35 colorless solids, mp 226ꢀ227 °C dec (lit.35 mp
Didodecyl disulfide:23 colorless solids, mp 30ꢀ31 °C (lit.23 mp
29ꢀ31 °C); 1H NMR (CDCl3) δ 0.88 (t, J = 7 Hz, 6H), 1.26 (m, 32H),
1.37 (quint, J = 7 Hz, 4H), 1.67 (quint, J = 7 Hz, 4H), 2.68 ppm (t, J = 7 Hz,
4H); 13C NMR (CDCl3) δ 14.1, 22.7, 28.5, 29.2, 29.2, 29.4, 29.5, 29.6,
29.6, 29.7, 31.9, 39.2 ppm.
240ꢀ242 °C dec); [R]20 ꢀ195.32 (c 1.00, 1 M HCl) [lit.35 [R]20
D
D
ꢀ205.17 (c 1.02, 1 M HCl)]; 1H NMR (4% NaOD in D2O) δ 2.85 (dd,
J = 14 and 8 Hz, 2H), 3.06 (dd, J = 14 and 5 Hz, 2H), 3.52 ppm (dd, J = 8
and 5 Hz, 2H); 13C NMR (4% NaOD in D2O) δ 44.0, 55.3, 181.1 ppm.
Glutathione disulfide:28,36 colorless solids, mp 170ꢀ172 °C
(lit.28 mp 178ꢀ180 °C); [R]20 ꢀ195.32 (c 1.00, 1 M HCl), [R]24
Bis(phenylmethyl) disulfide:23 colorless solids, mp 58ꢀ59 °C
1
(lit.23 mp 66ꢀ68 °C); H NMR (CDCl3) δ 3.61 (s, 4H), 7.24ꢀ7.35
D
D
ꢀ96.57 (c 2.03, H2O) [lit.36 [R]20D ꢀ108 (c 2, H2O)]; 1H NMR (D2O)
δ 2.13 (dd, J = 7 and 7 Hz, 2H), 2.14 (dd, J = 7 and 7 Hz, 2H), 2.49 (ddd,
J = 15, 7, and 6 Hz, 2H), 2.53 (ddd, J = 15, 7, and 6 Hz, 2H), 2.94 (dd, J =
14 and 9 Hz, 2H), 3.24 (dd, J = 14 and 5 Hz, 2H), 3.80 (dd, J = 6 and 6
Hz, 2H), 3.94 (s, 4H), 4.71 ppm (dd, J = 9 and 5 Hz, 2H); 13C NMR
(D2O) δ 26.5, 31.7, 39.1, 42.0, 53.0, 54.1, 172.9, 173.9, 175.2 ppm.
1,2-Dithiane:37 colorless solids, mp 26ꢀ27 °C (lit.37 mp
ppm (m, 10H); 13C NMR (CDCl3) δ 43.2, 127.4, 128.5, 129.3, 137.3 ppm.
Bis(2-hydroxyethyl) disulfide:24 colorless oil; 1H NMR (CDCl3)
δ 2.05 (br s, 2H), 2.89 (t, J = 6 Hz, 4H), 3.92 ppm (br t, J = 6 Hz, 4H);
13C NMR (CDCl3) δ 41.1, 60.3 ppm.
Bis(2-aminoethyl) disulfide:25 colorless oil; 1H NMR (CDCl3)
δ 1.39 (br s, 4H), 2.76 (t, J = 6 Hz, 4H), 3.02 ppm (t, J = 6 Hz, 4H);
13C NMR (CDCl3) δ 40.6, 42.5 ppm.
1
Dicyclohexyl disulfide:23 colorless oil; 1H NMR (CDCl3)
δ 1.16ꢀ1.40 (m, 10H), 1.57ꢀ1.66 (m, 2H), 1.73ꢀ1.84 (m, 4H),
1.99ꢀ2.10 (m, 4H), 2.62ꢀ2.72 ppm (m, 2H); 13C NMR (CDCl3)
δ 25.7, 26.1, 32.8, 50.0 ppm.
33ꢀ34 °C); H NMR (CDCl3) δ 1.97 (br s, 4H), 2.84 ppm (br s,
4H); 13C NMR (CDCl3) δ 27.8, 33.3 ppm.
1,2-Dithiepane:38. colorless oil; 1H NMR (CDCl3) δ 1.74ꢀ1.80
(m, 2H), 1.99ꢀ2.06 (m, 4H), 2.83 ppm (t, 4H); 13C NMR (CDCl3)
δ 26.2, 30.2, 39.4 ppm.
Di-tert-butyl disulfide:26 colorless oil; 1H NMR (CDCl3) δ 1.31
ppm (s, 18H); 13C NMR (CDCl3) δ 30.5, 46.1 ppm.
trans-1,2-Dithiane-4,5-diol:39 colorless solids, mp 128ꢀ130 °C
1
(lit.39 mp 128ꢀ130 °C); H NMR (CD3OD) δ 2.82ꢀ2.92 (m, 2H),
Bis(triphenylmethyl) disulfide:27 colorless solids, mp 153ꢀ155 °C
(lit.27 mp 158ꢀ159 °C); 1H NMR (CDCl3) δ 7.23ꢀ7.37 ppm (m, 30H);
13C NMR (acetone-d6) δ 82.2, 127.8, 128.5, 129.0, 148.9 ppm.
Diphenyl disulfide:23 colorless solids, mp 51ꢀ52 °C (lit.23 mp
59ꢀ61 °C); 1H NMR (CDCl3) δ 7.22 (m, 2H), 7.30 (m, 4H),
7.50ppm(m, 4H); 13C NMR (CDCl3) δ 127.1, 127.4, 129.0, 137.0 ppm.
Bis(4-methylphenyl) disulfide:7d colorless solids, mp 53ꢀ54 °C
(lit.7d mp 51ꢀ53 °C); 1H NMR (CDCl3) δ 2.33 (s, 6H), 7.11 (d, J = 8 Hz,
4H), 7.39 ppm (d, J = 8 Hz, 4H); 13C NMR (CDCl3) δ 21.1, 128.5, 129.8,
133.9, 137.4 ppm.
3.00ꢀ3.08 (m, 2H), 3.46ꢀ3.53 ppm (m, 2H); 13C NMR (CD3OD)
δ 41.7, 75.5 ppm.
Formation of Tellurone Oligomer and Its Reaction with
Dodecanethiol (Scheme 1). A CH2Cl2 solution (30 mL) of An2Te
(10.3 mg, 30.7 μmol) in the presence of TPP (0.1 mM) was irradiated
with a 500-W halogen lamp under aerobic conditions at 0 °C for 5 min.
After the solvent was evaporated, the residue was analyzed by 1H and 13
C
NMR spectroscopy and then dissolved in CH2Cl2 (3 mL). To this
solution was added an excess amount of dodecanethiol (47.3 mg, 234
μmol) and the solution was stirred at 0 °C for 5 min. The reaction
mixture was directly analyzed by 1H NMR spectroscopy, and the
amounts of didodecyl disulfide (60.4 μmol) and An2Te (30.7 μmol)
were determined by integration of the 1H NMR signals.
Bis(4-methoxyphenyl) disulfide:7b colorless solids, mp 34ꢀ35 °C
(lit.7b mp 41ꢀ43 °C); 1H NMR (CDCl3) δ 3.80 (s, 6H), 6.84 (d, J = 9 Hz,
4H), 7.40 ppm (d, J = 9 Hz, 4H); 13C NMR (CDCl3) δ 55.4, 114.6, 128.4,
132.6, 159.9 ppm.
Bis(4-chlorophenyl) disulfide:28 colorless solids, mp 65ꢀ66 °C
’ ASSOCIATED CONTENT
1
(lit.28 mp 71ꢀ72 °C); H NMR (CDCl3) δ 7.28 (d, J = 9 Hz, 4H),
7.40 ppm (d, J = 9 Hz, 4H); 13C NMR (CDCl3) δ 129.3 (overlapped),
S
Supporting Information. General experimental infor-
b
mation and copies of H and 13C NMR for disulfides and
1
133.6, 135.1 ppm.
Bis(4-(trifluoromethyl)phenyl) disulfide:29 colorless oil; H
1
(An2TeO2)n. This material is available free of charge via the
NMR (DMSO-d6) δ 7.64 (d, J = 9 Hz, 4H), 7.65 ppm (d, J = 9 Hz, 4H);
13C NMR (DMSO-d6) δ 124.1 (q, J = 272 Hz), 126.4, 126.8, 128.1
(q, J = 32 Hz), 140.7 ppm.
’ AUTHOR INFORMATION
Bis(4-(methylthio)phenyl) disulfide:30 colorless solids, mp
80ꢀ82 °C (lit.30 mp 90 °C); 1H NMR (CDCl3) δ 2.47 (s, 6H), 7.17
(d, J = 9 Hz, 4H), 7.39 ppm (d, J = 9 Hz, 4H); 13C NMR (CDCl3) δ 15.7,
126.9, 129.4, 133.4, 138.5 ppm.
Corresponding Author
*To whom correspondence should be addressed. E-mail: moba@
tokai-u.jp (M.O.), nishiyam@wing.ncc.u-tokai.ac.jp (K.N.), and
wataru.ando@aist.go.jp (W.A.).
Bis(2,6-dichlorophenyl) disulfide:7f colorless solids, mp 78ꢀ82 °C
(lit.7f mp 80ꢀ83 °C); 1H NMR (CDCl3) δ 7.20 (dd, J = 9 and 7 Hz, 2H),
7.34 (d, J = 9 Hz, 2H), 7.34 ppm (d, J = 7 Hz, 2H); 13C NMR (CDCl3)
δ 128.5, 131.1, 134.2, 141.4 ppm.
’ ACKNOWLEDGMENT
Bis(2-pyridinyl) disulfide:31 colorless solids, mp 53ꢀ54 °C (lit.31
M.O. would like to acknowledge Tokai University for financial
support.
mp 55ꢀ56 °C); 1H NMR (CDCl3) δ 7.11 (m, 2H), 7.59ꢀ7.65 (m, 4H),
4176
dx.doi.org/10.1021/jo200496r |J. Org. Chem. 2011, 76, 4173–4177