boxylate (2c): 1H NMR (500 MHz, CDCl3) δ 8.65 (s, br, 1H),
7.59 (s, 4H), 7.50 (t, J ) 2.4 Hz, 1H), 6.81 (t, J ) 2.4 Hz, 1H),
4.22 (q, J ) 7.3 Hz, 2H), 1.25 (t, J ) 7.3 Hz, 3H); 13C NMR
(125 MHz, CDCl3) δ 164.7, 138.5, 129.6, 128.7, 128.4, 125.7,
125.6, 125.5, 124.7, 124.6, 118.8, 113.9, 59.9, 14.4; HRMS
(ESI) for [M + H+] C14H13F3NO2: calcd, 284.0892; found,
284.0891.
Ethyl 4-[3-(trifluoromethyl)phenyl]-1H-pyrrole-3-car-
boxylate (2d): 1H NMR (500 MHz, CDCl3) δ 8.60 (s, br, 1H),
7.72 (s, 1H), 7.67 (d, J ) 7.3 Hz, 1H), 7.52 (m, 1H), 7.50 (t,
J ) 2.3 Hz, 1H), 7.44 (m, 1H), 6.79 (t, J ) 2.3 Hz, 1H), 4.20
(q, J ) 7.4 Hz, 2H), 1.23 (t, J ) 7.4 Hz, 3H); 13C NMR (125
MHz, CDCl3) δ 164.7, 135.6, 132.8, 130.1 (q, J ) 31 Hz),
128.1, 126.2, 125.8, 125.5, 123.3, 118.7, 114.1, 59.9, 14.2;
HRMS (ESI) for [M + H+] C14H13F3NO2: calcd, 284.0892;
found, 284.0891.
Ethyl 4-(2-methoxyphenyl)-1H-pyrrole-3-carboxylate (2e):
1H NMR (500 MHz, CDCl3) δ 8.75 (s, br, 1H), 7.40 (t, J )
2.3 Hz, 1H), 7.27 (m, 2H), 6.95 (t, J ) 7.4 Hz, 1H), 6.90 (d,
J ) 8.0 Hz, 1H), 6.72 (t, J ) 2.3 Hz, 1H), 4.14 (q, J ) 7.4 Hz,
2H), 1.15 (t, J ) 7.4 Hz, 3H); 13C NMR (125 MHz, CDCl3) δ
165.4, 157.3, 131.2, 128.2, 124.4, 124.2, 121.9, 120.9, 118.7,
115.5, 110.4, 59.6, 55.5, 14.3; HRMS (ESI) for [M + H+]
C14H16NO3: calcd, 246.1124; found, 246.1125.
Ethyl 4-(4-phenoxyphenyl)-1H-pyrrole-3-carboxylate (2g):
1H NMR (500 MHz, CDCl3) δ 9.14 (s, br, 1H), 7.44 (d, J )
8.5 Hz, 2H), 7.36 (s, 1H), 7.28 (t, J ) 8.0 Hz, 2H), 7.06 (t, J
) 7.4 Hz, 1H), 6.98 (t, J ) 7.4 Hz, 2H), 6.62 (s, 1H), 4.22 (q,
J ) 7.4 Hz, 2H), 1.26 (t, J ) 7.4 Hz, 3H); 13C NMR (125
MHz, CDCl3) δ 165.6, 157.4, 156.0, 130.8, 130.2, 129.9, 125.9,
123.3, 118.9, 118.6, 118.4, 113.2, 59.9, 14.5; HRMS (ESI) for
[M + H+] C19H18NO3: calcd, 308.1281; found, 308.1280.
Ethyl 4-tert-butyl-1H-pyrrole-3-carboxylate (2h): 1H NMR
(500 MHz, CDCl3) δ 8.20 (s, br, 1H), 7.46 (d, J ) 2.5 Hz,
1H), 6.54 (d, J ) 2.5 Hz, 1H), 4.24 (q, J ) 7.4 Hz, 2H), 1.38
(s, 9H), 1.27 (t, J ) 7.4 Hz, 3H); 13C NMR (125 MHz, CDCl3)
δ 165.0, 135.7, 126.8, 115.4, 113.9, 59.5, 31.4, 30.4, 14.5;
HRMS (ESI) for [M + H+] C11H18NO2: calcd, 196.1332; found,
196.1331.
Ethyl 4-iso-butyl-1H-pyrrole-3-carboxylate (2i): 1H NMR
(500 MHz, CDCl3) δ 8.81 (s, br, 1H), 7.37 (d, J ) 1.9 Hz,
1H), 6.50 (d, J ) 1.9 Hz, 1H), 4.24 (q, J ) 7.3 Hz, 2H), 2.56
(d, J ) 7.3 Hz, 2H), 1.86 (m, 1H), 1.33 (t, J ) 7.3 Hz, 3H),
0.90 (d, J ) 7.3 Hz, 6H); 13C NMR (125 MHz, CDCl3) δ 165.9,
125.0, 124.7, 117.8, 114.4, 59.5, 35.4, 29.1, 22.6, 14.5; HRMS
(ESI) for [M + H+] C11H18NO2: calcd, 196.1332; found,
196.1331.
Ethyl 4-(3,5-dimethoxyphenyl)-1H-pyrrole-3-carboxylate
(2f): 1H NMR (500 MHz, CDCl3) δ 8.57 (s, br, 1H), 7.47 (s,
1H), 6.79 (s, 1H), 6.66 (s, 2H), 6.40 (s, 1H), 4.22 (q, J ) 7.4
Hz, 2H), 1.25 (t, J ) 7.4 Hz, 3H); 13C NMR (125 MHz, CDCl3)
δ 164.8, 160.1, 136.7, 126.5, 125.4, 118.5, 114.1, 107.7, 98.9,
59.8, 55.4, 14.4; HRMS (ESI) for [M + H+] C15H18NO4: calcd,
276.1230; found, 276.1231.
Supporting Information Available
1H and 13C NMR spectra of 2a-j. This material is available
Received for review December 12, 2007.
OP7002826
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