PAPER
Synthesis of Fused Sulfur Heterocycles
1199
H, J = 5.2 Hz, ArCH2), 2.86 (t, 2 H, J = 5.8 Hz, SCH2), 2.43–2.37
(m, 2 H, SCH2CH2CH2Ar).
13C NMR (CDCl3): = 151.40 (Cq, Ar), 127.24, 125.24, 121.24,
118.10 (4 C, Ar), 117.47 (Cq, Ar), 64.94 (OCH2), 25.33 (SCH2).
13C NMR (CDCl3): = 136.31, 130.31, 125.67 (3 Cq, Ar), 121.17,
118.73, 117.78, 108.50 (4 C, Ar), 100.00 (Cq, Ar), 28.93 (NCH3),
26.59 (SCH2), 24.46 (ArCH2), 21.63 (SCH2CH2CH2Ar).
Anal. Calcd for C8H8OS: C, 63.13; H, 5.30. Found: C, 63.15; H,
5.12.
2,3-Dihydronaphtho[1,2-b][1,4]oxathiine (18b)
Yield: 91%; colorless crystals; mp 71–73 °C (dec.).
Anal. Calcd for C12H13NS: C, 70.89; H, 6.45. Found: C, 71.10; H,
6.46.
1H NMR (CDCl3): = 8.36 (d, 1 H, J = 8.3 Hz, ArH), 7.67 (d, 1 H,
J = 7.8 Hz, ArH), 7.46–7.33 (m, 2 H, ArH), 7.30 (d, 1 H, J = 8.6 Hz,
ArH), 7.06 (d, 1 H, J = 8.6 Hz, ArH), 4.53 (t, 2 H, J = 4.6 Hz,
OCH2), 3.16 (t, 2 H, J = 4.6 Hz, SCH2).
13C NMR (CDCl3): = 146.18, 132.00 (2 Cq, Ar), 127.49 (Ar),
125.92 (Cq, Ar), 125.78, 125.53, 125.27, 120.80, 120.39 (5 C, Ar),
111.43 (Cq, Ar), 65.37 (OCH2), 25.70 (SCH2).
2,3-Dihydropyrrolo[2,1-b][1,3]thiazole (14a)
Yield: 76%; colorless crystals; mp 57–59 °C.
1H NMR (CDCl3): = 6.73 (dd, 1 H, J = 1.4, 3.0 Hz, ArH), 6.25
(dd, 1 H, J = 3.0, 3.4 Hz, ArH), 5.86 (dd, 2 H, J = 1.4, 3.4 Hz, ArH),
4.15 (t, 2 H, J = 6.9 Hz, NCH2), 3.73 (t, 2 H, J = 6.9 Hz, SCH2).
13C NMR (CDCl3): = 116.02, 113.12 (2 C, Ar), 110.78 (Cq, Ar),
99.89 (Ar), 48.07 (ArCH2), 35.84 (SCH2).
Anal. Calcd for C12H10OS: C, 71.25; H, 4.98. Found: C, 71.21; H,
4.93.
Anal. Calcd for C6H7NS: C, 57.56; H, 5.64. Found: C, 57.45; H,
5.61.
2,3-Dihydronaphtho[2,1-b][1,4]oxathiine (18c)
Yield: 94%; colorless crystals; mp 64–66 °C (dec.).
3,4-Dihydro-2H-pyrrolo[2,1-b][1,3]thiazine (14b)
Yield: 81%; colorless crystals; mp 51–53 °C.
1H NMR (CDCl3): = 6.55 (dd, 1 H, J = 1.7, 2.9 Hz, ArH), 6.06
(dd, 1 H, J = 2.9, 3.6 Hz, ArH), 5.83 (dd, 2 H, J = 1.7, 3.6 Hz, ArH),
3.92 (t, 2 H, J = 5.9 Hz, NCH2), 2.91 (t, 2 H, J = 5.9 Hz, SCH2), 2.20
(tt, 2 H, J = 5.9, 5.9 Hz, SCH2CH2CH2N).
1H NMR (CDCl3): = 7.84 (d, 1 H, J = 8.4 Hz, ArH), 7.64 (d, 1 H,
J = 8.1 Hz, ArH), 7.44–7.37 (m, 2 H, ArH), 7.32 (dd, 1 H, J = 6.9,
8.1 Hz, ArH), 6.98 (d, 1 H, J = 8.9 Hz, ArH), 4.31 (t, 1 H, J = 4.7
Hz, OCH2), 3.01 (t, 1 H, J = 4.7 Hz, SCH2).
13C NMR (CDCl3): = 149.03, 131.10, 129.13 (3 Cq, Ar), 128.13,
126.11, 125.42, 123.85, 122.05, 119.56 (6 C, Ar), 110.43 (Cq, Ar),
64.94 (OCH2), 24.84 (SCH2).
13C NMR (CDCl3): = 121.25 (Ar), 117.72(Cq, Ar), 107.90, 105.47
(2 C, Ar), 45.20 (NCH2), 25.72 (SCH2), 25.14 (SCH2CH2CH2N).
Anal. Calcd for C12H10OS: C, 71.25; H, 4.98. Found: C, 70.96; H,
4.92.
Anal. Calcd for C7H9NS: C, 60.39; H, 6.52. Found: C, 60.11; H,
6.71.
Ring-Opening Reaction of Sulfonium Salts to the Amines 10;
General Procedure
1,2-Dihydro[1,4]thiazino[2,3,4-jk]carbazole (14c)
Yield: 63%; colorless crystals; mp 136–138 °C.
To a stirred solution of the corresponding five-membered cyclic sul-
fonium salt (2 mmol) in anhyd MeCN (10 mL) was added dropwise
Et2NH (1.1 mL, 10 mmol) while maintaining the temperature below
0 °C. The mixture was warmed to r.t., stirred for 1 h, and then sol-
vent was removed in vacuo. The crude product was purified by col-
umn chromatography on silica gel (eluent: CHCl3–MeOH, 10:1) to
yield the corresponding amine.
1H NMR (CDCl3): = 8.03 (d, 1 H, J = 7.8 Hz, ArH), 7.79 (d, 1 H,
J = 7.7 Hz, ArH), 7.41 (dd, 1 H, J = 8.1, 7.2 Hz, ArH), 7.27 (d, 1 H,
J = 8.1 Hz, ArH), 7.23–7.07 (m, 3 H, ArH), 4.39 (t, 2 H, J = 5.2 Hz,
NCH2), 3.22 (t, 2 H, J = 5.2 Hz, SCH2).
13C NMR (CDCl3): = 139.82, 134.05 (2 Cq, Ar), 125.72 (Ar),
123.51 (Cq, Ar), 122.47 (Ar), 121.64 (Cq, Ar), 120.85, 119.47,
119.40, 117.14 (4 C, Ar), 115.21 (Cq, Ar), 108.18 (Ar), 42.33
(NCH2), 25.74 (SCH2).
N,N-Diethyl-2-[5-methyl-3-(methylsulfanyl)-2-thienyl]-1-etha-
namine (10a)
Yield: 68%; colorless viscous oil.
Anal. Calcd for C14H11NS: C, 74.63; H, 4.92. Found: C, 74.52; H,
4.83.
1H NMR (CDCl3): = 6.52 (s, 1 H, ArH), 2.92 (t, 2 H, J = 7.9 Hz,
ArCH2CH2N), 2.64 (t, 2 H, J = 7.9 Hz, ArCH2), 2.57 (q, 4 H, J = 7.1
Hz, NCH2CH3), 2.36 (s, 3 H, SCH3), 2.30(s, 3 H, ArCH3), 1.05 (t, 6
H, J = 7.1 Hz, NCH2CH3).
13C NMR (CDCl3): = 139.03, 136.49, 128.32 (3 Cq, Ar), 127.55
(Ar), 53.96 (ArCH2CH2N), 46.82 (2 C, NCH2CH3), 25.94 (ArCH2),
19.11 (ArCH3), 15.20 (SCH3), 11.88 (2 C, NCH2CH3).
6,7-Dihydro-5H-[1,4]thiazepino[2,3,4-jk]carbazole (14d)
Yield: 11%; colorless crystals; mp 108–110 °C.
1H NMR (CDCl3): = 7.89 (d, 1 H, J = 7.8 Hz, ArH), 7.72 (d, 1 H,
J = 7.7 Hz, ArH), 7.36–7.06 (m, 4 H, ArH), 6.93 (dd, 1 H, J = 7.7,
7.5 Hz, ArH), 4.64 (t, 2 H, J = 6.0 Hz, NCH2), 3.26 (t, 2 H, J = 6.8
Hz, SCH2), 2.30–2.21 (m, 2 H, SCH2CH2CH2N).
13C NMR (CDCl3): = 141.25, 140.76 (2 Cq, Ar), 127.27, 125.84 (2
C, Ar), 124.06, 122.76, 121.06 (3 Cq, Ar), 120.30, 119.56, 119.03,
118.51, 108.55 (5 C, Ar), 42.56 (NCH2), 34.25 (SCH2), 29.18
(SCH2CH2CH2N).
Anal. Calcd for C12H21NS2: C, 59.21; H, 8.70. Found: C, 59.45; H,
8.68.
N,N-Diethyl-2-[2-(methylsulfanyl)-3-thienyl]-1-ethanamine
(10b)
Yield: 73%; colorless viscous oil.
Anal. Calcd for C15H13NS: C, 75.27; H, 5.47. Found: C, 75.66; H,
5.40.
1H NMR (CDCl3): = 7.21 (d, 1 H, J = 5.2 Hz, ArH), 6.87 (d, 1 H,
J = 5.2 Hz, ArH), 2.82 (t, 2 H, J = 8.0 Hz, ArCH2CH2N), 2.62 (t, 2
H, J = 8.0 Hz, ArCH2), 2.55 (q, 4 H, J = 6.8 Hz, NCH2CH3), 2.35
(s, 3 H, SCH3), 1.04 (t, 6 H, J = 6.8, NCH2CH3).
13C NMR (CDCl3): = 143.80, 130.94 (2 Cq, Ar), 128.76, 126.92 (2
C, Ar), 53.18 (ArCH2CH2N), 46.73 (2 C, NCH2CH3), 26.17
(ArCH2), 22.20 (SCH3), 11.72 (2 C, NCH2CH3).
2,3-Dihydro-1,4-benzoxathiin (18a)
Yield: 86%; colorless oil.
1H NMR (CDCl3): = 6.91 (dd, 1 H, J = 1.9, 8.3, ArH), 6.84 (ddd,
1 H, J = 1.6, 7.7, 8.3 Hz, ArH), 6.74–6.68 (m, 2 H, ArH), 4.21 (t, 1
H, J = 4.7 Hz, OCH2), 2.92 (t, 1 H, J = 4.7 Hz, SCH2).
Synthesis 2003, No. 8, 1191–1200 ISSN 1234-567-89 © Thieme Stuttgart · New York