I. Chiarotto et al. / Tetrahedron 65 (2009) 3704–3710
3709
156.2, 148.0, 133.0, 130.7, 130.0, 120.4, 115.1, 49.6. GC–MS (EI) m/z:
159.5 (d, 1J¼240.9 Hz), 151.3, 138.2 (d, 4J¼2.3 Hz), 128.2 (d,
3J¼13.4 Hz), 111.4 (d, 2J¼24.9 Hz), 110.2 (d, 3J¼9.3 Hz), 104.5 (d,
ꢃ
ꢃ
213 (Mþ þ2, 30%), 211 (Mþ , 89%), 135 (100%), 106 (15%). Anal. Calcd
for C9H6ClNO3: C, 51.08; H, 2.86; N, 6.62. Found: C, 51.12; H, 2.90; N,
6.60.
ꢃ
ꢃ
2J¼30.9 Hz), 30.3, 7.8. GC–MS (EI) m/z: 210 (Mþ þ1, 23%), 209 (Mþ
,
81%), 153 (100%), 124 (71%), 57 (100%), 29 (91%). Anal. Calcd for
C10H8FNO3: C, 57.42; H, 3.85; N, 6.70. Found: C, 57.48; H, 3.88; N, 6.68.
3.1.6. 3-Benzoylbenzo[d]oxazol-2(3H)-one 3af8,19
1H NMR (CDCl3, 200 MHz):
d
7.86–7.76 (m, 3H), 7.66–7.59 (m,
3.1.14. 5-Chloro-3-propionylbenzo[d]oxazol-2(3H)-one 3fb
1H), 7.52–7.45 (m, 2H), 7.29–7.24 (m, 3H). 13C NMR (CDCl3,
1H NMR (CDCl3, 200 MHz):
d
8.02 (d, 1H, J¼2.0 Hz), 7.37 (dd, 1H,
50.3 MHz):
d
171.6,167.6,143.9,142.7,133.5,132.1,129.5,128.3,125.8,
J¼8.6, 2.0 Hz), 7.07 (d, 1H, J¼8.6 Hz), 3.06 (q, 2H, J¼7.3 Hz), 1.23 (t,
ꢃ
125.2,124.7,115.0,110.1. GC–MS (EI) m/z: 239 (Mþ , 3%),134 (1%),106
(29%), 105 (100%), 77 (97%), 51 (11%). Anal. Calcd for C14H9NO3: C,
70.29; H, 3.79; N, 5.86. Found: C, 70.33; H, 3.81; N, 5.86.
3H, J¼7.3 Hz). 13C NMR (CDCl3, 50.3 MHz):
d 173.0, 150.8, 140.6,
130.2, 128.4, 125.0, 116.3, 110.5, 30.3, 7.8. GC–MS (EI) m/z: 227
ꢃ
ꢃ
(Mþ þ2, 2%), 225 (Mþ , 7%), 171 (29%), 169 (73%), 57 (100%), 29
(60%). Anal. Calcd for C10H8ClNO3: C, 53.23; H, 3.57; N, 6.21. Found:
C, 53.28; H, 3.61; N, 6.19.
3.1.7. Ethyl 5-(2-oxobenzo[d]oxazol-3(2H)-yl)pentanoate 3ag
1H NMR (CDCl3, 200 MHz):
d 7.15–7.02 (m, 3H), 6.94–6.90 (m,
1H), 4.04 (q, 2H, J¼7.2 Hz), 3.78 (t, 2H, J¼6.4 Hz), 2.30 (t, 2H,
3.1.15. 5-Bromo-3-propionylbenzo[d]oxazol-2(3H)-one 3gb
J¼6.4 Hz), 1.81–1.61 (m, 4H), 1.18 (t, 3H, J¼7.2 Hz). 13C NMR (CDCl3,
1H NMR (CDCl3, 200 MHz):
d
8.25 (d, 1H, J¼2.0 Hz), 7.37 (dd, 1H,
50.3 MHz):
d
172.9, 154.4, 142.6, 131.0, 123.6, 122.2, 109.8, 108.1,
J¼8.5, 2.0 Hz), 7.07 (d, 1H, J¼8.5 Hz), 3.10 (q, 2H, J¼7.2 Hz), 1.26 (t, 3H,
ꢃ
60.3, 41.7, 33.4, 27.0, 21.8, 14.0. GC–MS (EI) m/z: 264 (Mþ þ1, 24%),
J¼7.2 Hz). 13C NMR (CDCl3, 50.3 MHz):
d 172.9, 150.7, 141.1, 128.7, 127.9,
ꢃ
263 (Mþ , 56%), 218 (32%), 190 (16%), 176 (18%), 161 (100%), 148
ꢃ
ꢃ
118.9,117.3,110.9, 30.3, 7.8. GC–MS (EI) m/z:271(Mþ þ2,4%), 269(Mþ
,
(56%), 135 (56%), 129 (53%), 101 (61%). Anal. Calcd for C14H17NO4: C,
63.87; H, 6.51; N, 5.32. Found: C, 63.93; H, 6.56; N, 5.30.
4%), 215 (44%), 213 (43%), 57 (100%), 29 (43%). Anal. Calcd for
C10H8BrNO3: C, 44.47; H, 2.99; N, 5.19. Found: C, 44.51; H, 3.01; N, 5.21.
3.1.8. 3-Ethylbenzo[d]oxazol-2(3H)-one 3ah21
3.1.16. 6-Nitro-3-propionylbenzo[d]oxazol-2(3H)-one 3hb
1H NMR (CDCl3, 200 MHz):
d 7.24–7.03 (m, 3H), 6.97–6.94 (m,
1H NMR (CDCl3, 200 MHz):
d
8.21 (d, 2H, J¼1.4 Hz), 8.09 (d, 2H,
1H), 3.86 (q, 2H, J¼7.2 Hz), 1.35 (t, 3H, J¼7.2 Hz). 13C NMR (CDCl3,
J¼1.2 Hz), 3.14 (q, 2H, J¼7.2 Hz), 1.28 (t, 3H, J¼7.2 Hz). 13C NMR
50.3 MHz):
d 154.3, 142.7, 130.8, 123.7, 122.2, 109.9, 108.1, 37.1, 12.9.
ꢃ ꢃ
(CDCl3, 50.3 MHz):
d
172.9, 150.5, 145.0, 141.9, 132.6, 121.1, 115.8,
GC–MS (EI) m/z: 164 (Mþ þ1, 6%), 163 (Mþ , 100%), 148 (55%), 135
(62%), 91 (13%). Anal. Calcd for C9H9NO2: C, 66.25; H, 5.56; N, 8.58.
Found: C, 66.30; H, 5.60; N, 8.58.
ꢃ
106.0, 30.6, 7.8. GC–MS (EI) m/z: 236 (Mþ , 2%),164 (2%),106 (2%), 57
(100%), 29 (15%). Anal. Calcd for C10H8N2O5: C, 50.85; H, 3.41; N,
11.86. Found: C, 50.89; H, 3.46; N, 11.85.
3.1.9. 3-Methylbenzo[d]oxazol-2(3H)-one 3ai
3.1.17. 1-Propionyl-1H-benzo[d]imidazol-2(3H)-one 3ib
1H NMR (CDCl3, 200 MHz):
d 7.19–7.07 (m, 3H), 6.95–6.91 (m,
1H NMR (acetone-d6, 200 MHz):
d 10.1 (br s, 1H), 8.13–8.08 (m,
1H), 3.37 (s, 1H). 13C NMR (CDCl3, 50.3 MHz):
d
154.5, 142.62, 131.70,
1H), 7.21–7.04 (m, 3H), 3.13 (q, 2H, J¼7.3 Hz), 1.22 (t, 3H, J¼7.3 Hz).
ꢃ
123.79, 122.43, 109.87, 108.01, 28.03. GC–MS (EI) m/z: 150 (Mþ þ1,
13C NMR (acetone-d6, 50.3 MHz):
d
175.1, 153.4, 129.9, 128.7, 125.1,
ꢃ
7%), 149 (Mþ , 100%), 120 (13%), 93 (6%). Anal. Calcd for C8H7NO2: C,
ꢃ
122.6, 116.2, 109.8, 31.2, 8.6. GC–MS (EI) m/z: 190 (Mþ , 5%), 135
(11%), 134 (100%), 106 (13%), 57 (3%). Anal. Calcd for C10H10N2O2: C,
63.15; H, 5.30; N, 14.73. Found: C, 63.21; H, 5.35; N, 14.74.
64.42; H, 4.73; N, 9.39. Found: C, 64.45; H, 4.77; N, 9.37.
3.1.10. 4-Methyl-3-propionylbenzo[d]oxazol-2(3H)-one 3bb
1H NMR (CDCl3, 200 MHz):
d 7.17–6.99 (m, 3H), 3.17 (q, 2H,
3.1.18. 1-(2-Thioxobenzo[d]oxazol-3(2H)-yl)propan-1-one 3jb
J¼7.3 Hz), 2.36 (s, 3H), 1.28 (t, 3H, J¼7.3 Hz). 13C NMR (CDCl3,
1H NMR (CDCl3, 200 MHz):
d 8.10–8.05 (m, 1H), 7.30–7.26 (m,
50.3 MHz):
d
173.1, 152.0, 143.3, 127.9, 126.5, 126.3, 125.2, 107.4, 31.1,
3H), 3.50 (q, 2H, J¼7.3 Hz), 1.30 (t, 3H, J¼7.3 Hz). 13C NMR (CDCl3,
ꢃ
21.2, 8.7. GC–MS (EI) m/z: 205 (Mþ , 2%), 149 (100%), 121 (2%), 57
(23%). Anal. Calcd for C11H11NO3: C, 64.38; H, 5.40; N, 6.83. Found:
C, 64.40; H, 5.40; N, 6.82.
50.3 MHz):
d
178.8, 174.9, 148.6, 130.0, 126.0, 125.5, 116.4, 109.6,
ꢃ
33.1, 8.3. GC–MS (EI) m/z: 207 (Mþ , 2%), 179 (5%), 151 (100%), 135
(5%), 57 (23%). Anal. Calcd for C10H9NO2S: C, 57.95; H, 4.38; N, 6.76.
Found: C, 57.99; H, 4.41; N, 6.74.
3.1.11. 5-Methyl-3-propionylbenzo[d]oxazol-2(3H)-one 3cb
1H NMR (CDCl3, 200 MHz):
d 7.84 (s, 1H), 7.10–6.89 (m, 3H), 3.87
3.1.19. 3-Propionylbenzo[d]thiazol-2(3H)-one 3kb
(q, 2H, J¼7.3 Hz), 2.36 (s, 3H), 1.23 (t, 3H, J¼7.3 Hz). 13C NMR (CDCl3,
1H NMR (CDCl3, 200 MHz):
d
8.27 (d, 1H, J¼7.9 Hz), 7.34–7.18 (m,
50.3 MHz):
d
173.4, 151.5, 140.2, 134.7, 127.6, 125.4, 116.3, 109.1, 30.3,
3H), 3.12 (q, 2H, J¼7.3 Hz), 1.25 (t, 3H, J¼7.3 Hz). 13C NMR (CDCl3,
ꢃ
21.4, 7.9. GC–MS (EI) m/z: 205 (Mþ , 14%), 150 (21%), 149 (100%), 57
(29%). Anal. Calcd for C11H11NO3: C, 64.38; H, 5.40; N, 6.83. Found:
C, 64.42; H, 5.42; N, 6.83.
50.3 MHz):
d
175.0, 170.9, 134.9, 126.9, 125.3, 121.9, 117.7, 32.6, 8.5.
ꢃ
GC–MS (EI) m/z: 207 (Mþ , 6%), 151 (100%), 123 (8%), 57 (43%). Anal.
Calcd for C10H9NO2S: C, 57.95; H, 4.38; N, 6.76. Found: C, 58.01; H,
4.44; N, 6.76.
3.1.12. 6-Methyl-3-propionylbenzo[d]oxazol-2(3H)-one 3db
1H NMR (acetone-d6, 200 MHz):
d
7.88 (d, 1H, J¼8.1 Hz), 7.14 (s,1H),
3.1.20. 3-Methyl-1-propionylimidazolium chloride22
7.08 (d, 1H, J¼8.1 Hz), 3.09 (q, 2H, J¼7.3 Hz), 2.38 (s, 3H), 1.20 (t, 3H,
1H NMR (CDCl3, 200 MHz):
d 11.06 (s, 1H), 7.65 (s, 1H), 6.98 (s,
J¼7.3 Hz). 13C NMR (acetone-d6, 50.3 MHz):
d
174.0,152.2,143.4,136.1,
1H), 6.80 (s, 1H), 3.60 (s, 1H), 2.22 (q, 2H, J¼7.6 Hz), 1.02 (t, 3H,
ꢃ
126.8, 125.7, 116.0, 110.9, 30.6, 21.4, 8.2. GC–MS (EI) m/z: 205 (Mþ
,
J¼7.6 Hz). 13C NMR (CDCl3, 50.3 MHz):
d 178.2, 137.3, 127.0, 120.3,
33.6, 27.9, 9.2. Anal. Calcd for C7H10ClN2O: C, 48.42; H, 5.81; N,
16.13. Found: C, 48.49; H, 5.86; N, 16.11.
24%), 150 (65%), 149 (100%), 57 (92%). Anal. Calcd for C11H11NO3: C,
64.38; H, 5.40; N, 6.83. Found C11H11NO3: C, 64.44; H, 5.43; N, 6.81.
3.1.13. 5-Fluoro-3-propionylbenzo[d]oxazol-2(3H)-one 3eb
1H NMR (CDCl3, 200 MHz):
d
7.83 (dd, 1H, J¼8.5, 2.7 Hz), 7.13 (dd,
3.1.21. 5-Chloro-3-ethylbenzo[d]oxazol-2(3H)-one 3fh
1H NMR (CDCl3, 200 MHz):
d 7.25–7.03 (m, 3H), 6.95 (s, 1H), 3.85
1H, J¼9.0, 4.3 Hz), 6.93 (ddd, 1H, J¼9.0, 9.0, 2.7 Hz), 3.10 (q, 2H,
(q, 2H, J¼7.2 Hz), 1.34 (t, 3H, J¼7.2 Hz). 13C NMR (CDCl3, 50.3 MHz):
J¼7.2 Hz), 1.26 (t, 3H, J¼7.2 Hz). 13C NMR (CDCl3, 50.3 MHz):
d 173.1,