I. Cikotiene
FULL PAPER
1-(Thieno[3,2-c][1,2]oxazol-3-yl)pentan-1-one (9b): White solid;
yield 99%; m.p. 62–63 °C. H NMR (300 MHz, CDCl3, 25 °C): δ
25 °C): δ = 3.99 (s, 3 H, OCH3), 4.00 (s, 3 H, OCH3), 6.88 (s, 1
H,ArH), 7.31 (s, 1 H, ArH), 7.53–7.56 (m, 2 H, ArH), 7.61–7.68
1
= 0.95 (t, J = 7.5 Hz, 3 H, CH2CH2CH2CH3), 1.44 (sext., J = (m, 1 H,ArH), 8.28–8.31 (m, 2 H, ArH), ppm. 13C NMR (75 Hz,
7.5 Hz, 2 H, CH2CH2CH2CH3), 1.76 (pent., J = 7.5 Hz, 2 H, CDCl3, 25 °C): δ = 56.3, 56.5, 91.7, 96.3, 119.2, 127.5, 128.6, 130.0,
CH2CH2CH2CH3), 3.04 (t, J = 7.5 Hz, 2 H, CH2CH2CH2CH3), 133.5, 136.2, 153.5, 155.2, 155.3, 181.6 ppm. IR (KBr): νmax = 1650
˜
7.09 [d, J = 5.4 Hz, 1 H, C(6)-H], 7.63 [d, J = 5.4 Hz, 1 H, C(5)-
(C=O) cm–1. HRMS (ES): calcd. for C16H14NO4 [M + H]+
H] ppm. 13C NMR (75 Hz, CDCl3, 25 °C): δ = 13.8, 22.3, 25.5, 284.0917; found 284.0929.
39.3, 111.9, 123.4, 142.7, 157.4, 170.9, 188.6 ppm. IR (KBr): ν
˜
max
(2,1-Benzisoxazol-3-yl)cyclopropylmethanone (11b): Yellowish solid;
yield 99%; m.p. 79–80 °C. H NMR (300 MHz, CDCl3, 25 °C): δ
= 1.23–1.28 (m, 2 H, c-Pr), 1.40–1.43 (m, 2 H, c-Pr), 3.04–3.13 (m,
1 H, c-Pr), 7.24–7.29 (m, 1 H, ArH), 7.39–7.44 (m, 1 H, ArH), 7.74
(d, J = 9.0 Hz, 1 H, ArH), 8.04 (d, J = 8.7 Hz, 1 H, ArH) ppm.
13C NMR (75 Hz, CDCl3, 25 °C): δ = 12.8, 18.9, 115.8, 118.6,
=
1681 (C=O) cm–1. HRMS (ES): calcd. for C10H12NO2S
1
[M + H]+ 210.0583; found 210.0577.
(4-Methylphenyl)(thieno[2,3-c][1,2]oxazol-3-yl)methanone
(9c):
White solid; yield 92%; m.p. 117–118 °C. 1H NMR (300 MHz,
CDCl3, 25 °C): δ = 2.49 (s, 3 H, CH3), 7.14 [d, J = 5.7 Hz, 1 H,
C(6)-H], 7.39 (d, J = 8.1 Hz, 2 H, ArH), 7.69 [d, J = 5.7 Hz, 1 H,
C(5)-H], 8.27 (d, J = 8.1 Hz, 2 H, ArH) ppm. 13C NMR (75 Hz,
CDCl3, 25 °C): δ = 21.8, 111.9, 126.8, 129.6, 130.2, 132.5, 143.0,
121.4, 128.4, 131.3, 157.6, 160.1, 190.1 ppm. IR (KBr): νmax = 1671
˜
(C=O) cm–1. HRMS (ES): calcd. for C11H10NO2 [M + H]+
188.0706; found 188.0752.
145.2, 158.5, 170.4, 178.9 ppm. IR (KBr): νmax = 1636 (C=O) cm–1.
˜
(Isoxazolo[4,3-b]pyridin-3-yl)phenylmethanone (12a): Beige solid;
HRMS (ES): calcd. for C13H10NO2S [M + H]+ 244.0427; found
244.0439.
1
yield 92%; m.p. 95–96 °C. H NMR (300 MHz, CDCl3, 25 °C): δ
= 7.37 [dd, J = 9.15, 3.6 Hz, 1 H, C(6)-H], 7.54–7.59 (m, 2 H,
ArH), 7.66–7.71 (m, 1 H, ArH), 7.14 [dd, J = 9.15, 1.5 Hz, 1 H,
C(7)-H], 8.20–8.23 (m, 2 H, ArH), 8.84 [dd, J = 3.6, 1.5 Hz, 1 H,
C(5)-H] ppm. 13C NMR (75 Hz, CDCl3, 25 °C): δ = 124.2, 125.8,
128.0, 128.7, 130.4, 134.2, 135.8, 151.4, 155.6, 160.4, 181.1 ppm.
(4-Ethylphenyl)(thieno[2,3-c][1,2]oxazol-3-yl)methanone (9d): White
solid; yield 95%; m.p. 69–70 °C. 1H NMR (300 MHz, CDCl3,
25 °C): δ = 1.29 (t, J = 7.8 Hz, 3 H, CH3), 2.75 (q, J = 7.8 Hz, 2
H, CH2), 7.10 [d, J = 5.7 Hz, 1 H, C(6)-H], 7.38 (d, J = 8.1 Hz, 2
H, ArH), 7.66 [d, J = 5.7 Hz, 1 H, C(5)-H], 8.27 (d, J = 8.1 Hz, 2
H, ArH) ppm. 13C NMR (75 Hz, CDCl3, 25 °C): δ = 14.9, 28.9,
111.8, 126.7, 128.3, 130.3, 132.5, 143.0, 151.2, 158.4, 170.3,
IR (KBr): ν
= 1661 (C=O) cm–1. HRMS (ES): calcd. for
˜
max
C13H9N2O2 [M + H]+ 225.0659; found 225.0677.
1-([1,2]Oxazolo[4,3-b]pyridin-3-yl)pentan-1-one (12b): White solid;
178.8 ppm. IR (KBr): νmax = 1637 (C=O) cm–1. HRMS (ES): calcd.
˜
1
yield 93%; m.p. 73–74 °C. H NMR (300 MHz, CDCl3, 25 °C): δ
for C14H12NO2S [M + H]+ 258.0583; found 258.0569.
= 0.95 (t, J = 7.5 Hz, 3 H, CH2CH2CH2CH3), 1.45 (sext., J =
7.5 Hz, 2 H, CH2CH2CH2CH3), 1.79 (pent., J = 7.5 Hz, 2 H,
CH2CH2CH2CH3), 3.32 (t, J = 7.5 Hz, 2 H, CH2CH2CH2CH3),
7.32 [dd, J = 9.15; 3.6 Hz, 1 H, C(6)-H], 8.09 [dd, J = 9.15; 1.5 Hz,
1 H, C(7)-H], 8.81 [dd, J = 3.6; 1.5 Hz, 1 H, C(5)-H] ppm. 13C
NMR (75 Hz, CDCl3, 25 °C): δ = 13.8, 22.3, 25.8, 40.7, 124.4,
(2-Pyridinyl)(thieno[2,3-c][1,2]oxazol-3-yl)methanone (9e): White
solid; yield 88%; m.p. 195–196 °C. 1H NMR (300 MHz, CDCl3,
25 °C): δ = 7.15 [d, J = 5.7 Hz, 1 H, C(6)-H], 7.59–7.64 (m, 1 H,
ArH), 7.61 [d, J = 5.7 Hz, 1 H, C(5)-H], 7.95–8.00 (m, 1 H, ArH),
8.31–8.34 (m, 1 H, ArH), 8.85 (ddd, J = 4.5, 1.8, 0.9 Hz, 1 H,
ArH) ppm. 13C NMR (75 Hz, CDCl3, 25 °C): δ = 112.6, 123.7,
127.9, 128.9, 137.6, 143.2, 148.3, 151.9, 154.8, 170.3, 176.4 ppm.
125.6, 132.6, 151.6, 155.4, 159.5, 188.7 ppm. IR (KBr): νmax = 1687
˜
(C=O) cm–1. HRMS (ES): calcd. for C11H13N2O2 [M + H]+
205.0972; found 205.0970.
IR (KBr): ν
= 1656 (C=O) cm–1. HRMS (ES): calcd. for
˜
max
C11H7N2O2S [M + H]+ 231.0223; found 231.0233.
(4-Methylphenyl)([1,2]oxazolo[4,3-b]pyridin-3-yl)methanone (12c):
Beige solid; yield 87%; m.p. 117–119 °C. 1H NMR (300 MHz,
CDCl3, 25 °C): δ = 2.49 (s, 3 H, CH3), 7.35–7.41 (m, 3 H, ArH),
8.14–8.18 (m, 3 H, ArH), 8.85–8.86 [m, 1 H, C(5)-H] ppm. 13C
NMR (75 Hz, CDCl3, 25 °C): δ = 21.8, 124.2, 125.7, 129.4, 130.5,
2,2-Dimethyl-1-thieno[2,3-c][1,2]oxazol-3-ylpropan-1-one (9f): White
1
solid; yield 99%; m.p. 75 °C. H NMR (300 MHz, CDCl3, 25 °C):
δ = 1.44 (s, 9 H, tBu), 7.06 [d, J = 5.4 Hz, 1 H, C(6)-H], 7.63 [d, J
= 5.4 Hz, 1 H, C(5)-H] ppm. 13C NMR (75 Hz, CDCl3, 25 °C): δ
= 25.9, 43.6, 111.9, 126.5, 143.2, 157.7, 170.1, 193.6 ppm. IR
133.2, 133.4, 145.4, 151.3, 155.4, 160.7, 180.7 ppm. IR (KBr): ν
˜
max
1664 (C=O) cm–1. HRMS (ES): calcd. for
=
1648 (C=O) cm–1. HRMS (ES): calcd. for C14H11N2O2
(KBr):
ν
=
˜
max
C10H12NO2S [M + H]+ 210.0583; found 210.0575.
[M + H]+ 239.0815; found 239.0874.
Phenyl(thieno[2,3-c][1,2]oxazol-3-yl)methanone (10a): Beige solid;
yield 88%; m.p. 53–55 °C. H NMR (300 MHz, CDCl3, 25 °C): δ
(4-Ethylphenyl)([1,2]oxazolo[4,3-b]pyridin-3-yl)methanone (12d): Be-
ige solid; yield 88%; m.p. 91–92 °C. H NMR (300 MHz, CDCl3,
1
1
= 7.14 [d, J = 5.4 Hz, 1 H, C(5)-H], 7.40 [d, J = 5.4 Hz, 1 H, C(4)-
H], 7.54–7.60 (m, 2 H, ArH), 7.67–7.70 (m, 1 H, ArH), 8.23–8.26
(m, 2 H, ArH) ppm. 13C NMR (75 Hz, CDCl3, 25 °C): δ = 115.0,
128.8, 130.0, 132.8, 133.9, 135.6, 136.8, 148.6, 156.3, 180.3 ppm.
25 °C): δ = 1.28 (t, J = 7.8 Hz, 3 H, CH3), 2.74 (q, J = 7.8 Hz, 2
H, CH2), 7.32–7.39 (m, 3 H, ArH), 8.11–8.16 (m, 3 H, ArH), 8.81–
8.83 [m, 1 H, C(5)-H] ppm. 13C NMR (75 Hz, CDCl3, 25 °C): δ =
14.9, 29.0, 124.2, 125.7, 127.3, 128.2, 130.6, 133.4, 151.3, 151.5,
= 1652 (C=O) cm–1. HRMS (ES): calcd. for
155.4, 160.7, 180.7 ppm. IR (KBr): ν
= 1646 (C=O) cm–1.
IR (KBr): ν
˜
max
˜
max
C12H8NO2S [M + H]+ 230.0270; found 230.0266.
HRMS (ES): calcd. for C15H13N2O2 [M + H]+ 253.0972; found
253.0971.
Cyclopropyl(thieno[2,3-c][1,2]oxazol-3-yl)methanone (10b): Beige so-
lid; yield 91%; m.p. 61–63 °C. 1H NMR (300 MHz, CDCl3, 25 °C):
δ = 1.17–1.23 (m, 2 H, c-Pr), 1.33–1.39 (m, 2 H, c-Pr), 2.84–2.92
(m, 1 H, c-Pr), 7.10 [d, J = 5.4 Hz, 1 H, C(5)-H], 7.36 [d, J =
5.4 Hz, 1 H, C(4)-H] ppm. 13C NMR (75 Hz, CDCl3, 25 °C): δ =
12.9, 18.7, 114.6, 116.3, 129.5, 136.6, 155.9, 188.9 ppm. IR (KBr):
Cyclopropyl([1,2]oxazolo[4,3-b]pyridin-3-yl)methanone (12e): Beige
solid; yield 94%; m.p. 129–130 °C. 1H NMR (300 MHz, CDCl3,
25 °C): δ = 1.20–1.27 (m, 2 H, c-Pr), 1.43–1.46 (m, 2 H, c-Pr), 3.44–
3.53 (m, 1 H, c-Pr), 7.33 [dd, J = 9.15, 3.9 Hz, 1 H, C(6)-H], 8.10
[dd, J = 9.15, 1.5 Hz, 1 H,C(7)-H], 8.81 [dd, J = 3.9, 1.5 Hz, 1 H,
C(5)-H] ppm. 13C NMR (75 Hz, CDCl3): δ = 13.3, 19.6, 124.4,
ν
max = 1663 (C=O) cm–1. HRMS (ES): calcd. for C9H8NO2S [M +
˜
H]+ 194.0270; found 194.0288.
125.5, 132.7, 151.5, 155.3, 159.6, 188.4 ppm. IR (KBr): νmax = 1672
˜
(5,6-Dimethoxy-2,1-benzisoxazol-3-yl)phenylmethanone (11a): Beige
(C=O) cm–1. HRMS (ES): calcd. for C10H9N2O2 [M + H]+
189.0658; found 189.0666.
solid; yield 87%; m.p. 165–166 °C. 1H NMR (300 MHz, CDCl3,
2772
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Eur. J. Org. Chem. 2012, 2766–2773