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(m, 2H, H-5, H-6); 7.90 (d, J¼9.2 Hz, 2H, H-20, H-60); 7.93 (m, 1H, H-
H-2); 7.80 (d, J¼7.9 Hz, 1H, H-4); 8.34 (d, J¼4.8 Hz, 1H, H-6). 13C
7); 8.28 (m, 1H, H-4); 8.33 (s, 1H, H-2). 13C NMR (CDCl3, 100 MHz)
RMN (CDCl3, 75.5 MHz) d (ppm), 55.3 (C-3); 116.9 (CH, C-5); 124.5
d
(ppm), 2.63 (CH2); 55.8 (CH3eO); 113.1 (CH, C-7); 114.1 (C-3);
(C-3a); 130.6 (CH, C-2); 131.1 (CH, C-4); 143.2 (CH, C-6); 146.7 (C-
7a). 2-Iodo-1H-pyrrolo[2,3-b]pyridine (17).16 The compound 17 was
obtained as a solid in <2% yield. Mp¼112e114 ꢀC (hexane/ethyl
114.9 (CH, C-30, C-50); 117.4 (CH, C-4); 123.2 (CH, C-6); 124.7 (CH,
C-5); 126.0 (CH, 127.6 (C-3a)); 128.7 (C-10); 129.6 (CH (ꢂ2), C-20, C-
60); 132.8 (C, C-2); 134.8 (C-7a); 164.8 (C-40); 188.5 (CO). HMRS
(C17H14INO4S) Calcd 454.9688, Found 454.9702.
acetate 1:1) (115e116 ꢀC).16 1H RMN (CDCl3, 300 MHz)
d (ppm), 6.54
(s, 1H, H-3); 7.28 (t, J¼8.0 Hz, 1H, H-5); 7.50 (m, 2H, H-30 and H-50);
7.72e7.81 (m, 2H, H-4, H-40); 7.89 (d, J¼7.5 Hz, 2H, H-20 and H-60);
4.3.5. 2-(2-Iodo-1H-indol-3-yl) acetonitrile (10).13 Following the
general procedure, compound 10 was obtained as a yellow solid in
60% yield. Mp:118e120 ꢀC (ethylacetate), (Lit.116e118 ꢀC)13 1HRMN
8.43 (d, J¼8.0 Hz,1H, H-6). 13C RMN (CDCl3, 75.5 MHz)
d (ppm), 76.2
(C); 119.3 (CH, C-3), 120.6 (CH, C-5); 123.9 (C, C-3a), 127.8 (CH, C-4);
128.1 (CH, C-20, C-60); 129.4 (CH, C-30, C-50); 134.8 (CH, C-40); 138.9
(C-10); 149.5 (C, C-7a). Anal.Calcd(%) for C7H4I2N2: C, 22.73; H, 1.09;
N, 7.57. Found: C, 23.02; H, 1.34; N, 7.34.
(CDCl3, 300 MHz) d (ppm), 3.88 (s, 2H, CH2CN); 7.59e7.17 (m, 4H, H-
Ar (ꢂ4)); 8.25 (s, 1H, NH). 13C RMN (CDCl3, 75.5 MHz)
d (ppm), 14.7
(CH2); 77.3 (C-2); 104.9 (C-3); 111.9 (CH, C-7); 118.4 (CH, C-4); 120.5
(CH, C-6); 123.2 (CN); 123.2 (CH, C-5); 126.5 (C-3a); 136.6 (C-7a).
4.3.11. 2,3-Diiodo-1-(phenylsulfonyl)-1H-pyrrolo[2,3-b]
pyridine
(19). Following the general procedure from 7-azaindole but using
excess of ICl (2.2 equiv), compound 19 was obtained as a solid in
4.3.6. 2-Iodo-2-(2-iodo-1H-indol-3-yl)acetonitrile (11). Following
the general procedure from the 2-indolylacetonitril but using ex-
cess of ICl (1.4 equiv), compound 11 was obtained as a solid in 39%
89% yield. 1H RMN (CDCl3, 300 MHz)
d
(ppm), 6.95 (dd, J1¼4.86 Hz,
J2¼7.89 Hz, 1H, H-5); 7.50 (m, 3H, H-30, H-50, H-40); 7.84 (d,
yield. 1H RMN ((CD6)2CO, 300 MHz)
d (ppm), 4.15 (s, 1H, CHCN);
J¼7.89 Hz, 1H, H-4); 8.18 (m, 2H, H-20, H-60); 8.43 (d, J¼4.86 Hz, 1H,
7.22 (d, J¼8.2 Hz, 1H, H-7); 7.40e7.31 (m, 1H, H-5); 7.60e7.54 (m,
H-6). 13C RMN (CDCl3, 75.5 MHz)
d (ppm), 73.4 (C); 109 (C), 120.9
1H, H-6); 7.85 (t, J¼8.2 Hz, 1H, H-4). 13C NMR (CDCl3, 75,5 MHz)
(CH, C-5); 123.3 (C, C-3a), 126.1 (CH, C-4); 128.9 (CH, C-20, C-60);
129.1 (CH, C-30, C-50); 134.8 (CH, C-40); 138.3 (C-10); 141.1 (CH, C-6);
149.2 (C, C-7a). Anal.Calcd(%) for C13H8I2N2O2S: C, 30.61; H, 1.58; N,
5.49. Found: C, 31.10; H, 1.88; N, 5.87.
d
(ppm), 25.4 (CH-I); 78.1 (C-2); 109.5 (CH, C-7); 114.0 (C-3); 117.1
(CN); 118.7 (CH, C-4); 122.5 (CH, C-6); 124.2 (CH, C-5); 128.4 (C-3a);
138.2 (C, C-7a). HMRS (C10H6I2N2) Calcd 407.8620, Found 407.8647.
4.3.7. 3-(2-Bromoethyl)-2-iodo-1H-indole (12). Following the gen-
eral procedure from the 3-(2-bromoethyl)indole with ICl (1 equiv),
compound 12 was obtained as yellow oil in 50% yield. 1H RMN
4.3.12. 1-Ethyl-5-iodo-2-methyl-3-(methylsulfonyl)-1H-pyrrole
(20). Following the general procedure from the substituted pyrrole,
the compound 20 was obtained as yellow oil in 78% yield. 1H RMN
(CDCl3, 300 MHz)
d
(ppm), 3.32 (t, J¼7.7 Hz, 2H, CH2-Ar); 3.63 (t,
(CDCl3, 300 MHz)
CH3eAr); 3.01 (s, 3H, CH3S); 3.95 (q, J¼7.3 Hz, 2H, CH2N); 6.39 (s,
1H, H-3). 13C RMN (CDCl3, 75.5 MHz)
(ppm), 10.7 (CH3); 15.9
(CH3); 42.6 (CH2eN); 44.9 (CH3eS); 117.6 (CH, C-4); 121.3 (C-3);
122.8 (C-5); 134.1 (C-2). Anal.Calcd(%) for C8H12INO2S: C, 30.68; H,
3.86; N, 4.47. Found: C, 30.45; H, 3.97; N, 4.89.
d
(ppm), 1.28 (t, J¼7.3 Hz, 3H, CH3); 2.48 (s, 3H,
J¼7.7 Hz, 2H, CH2Br); 7.24 (m, 2H, H-5, H-6); 7.36 (d, J¼7.9 Hz, 1H,
H-7); 7.50 (d, J¼7.9 Hz, 1H, H-4); 8.03 (s, 1H, NH). 13C RMN (CDCl3,
d
75.5 MHz)
d
(ppm), 28.7 (CH2); 32.5 (CH2eBr); 69.8 (C-2); 109.4
(CH, C-7); 115.4 (C-3); 119.0 (CH, C-4); 121.2 (CH, C-6); 124.4 (CH, C-
5); 126.2 (C-3a); 139.7 (C-7a). Anal. Calcd(%) forC10H9BrIN: C, 34.32;
H, 2.59; N, 4.00. Found: 34.60; H, 2.21; N, 4.36.
4.3.13. 4-Iodo-1-methyl-1H-pyrrole-2-carbaldehyde (21).17 Following
the general procedure from N-methylpyrrole-3-carbaldehyde, the
compound 21 was obtained as solid in 63% yield. Mp¼72e75 ꢀC. 1H
4.3.8. N-(2-(2-Iodo-1H-indol-3-yl)ethyl)acetamide (13). Following
the general procedure from the N-(2-(1H-indol-3-yl)ethyl)acetamide
compound 13 was obtained as a solid in 57% yield. Mp: 54e56 ꢀC
RMN (CDCl3, 300 MHz) d (ppm), 3.94 (s, 3H, CH3); 6.91 (s, 1H, H-3);
(ethyl acetate). 1H RMN (CDCl3, 300 MHz)
d
(ppm), 1.92 (s, 3H, CH3);
6.98 (s, 1H, H-5); 9.50 (s, 1H, CHO). 13C RMN (CDCl3, 75.5 MHz)
d (ppm), 36.9 (CH3); 77,0 (C, C-4); 130.3 (CH, C-3); 133.9 (C, C-2);
2.96 (t, J¼6.0 Hz, 2H, CH2eAr); 3.55 (t, J¼6.0 Hz, 2H, CH2NH); 5.50 (s,
1H, NH); 7.20e7.11 (m, 2H, H-5, H-6); 7.29 (d, J¼6.0 Hz,1H, H-7); 7.51
(d, J¼6.0 Hz, 1H, H-4); 8.28 (s, 1H, NH). 13C RMN (CDCl3, 75.5 MHz)
136.3 (CH, C-5); 179.1 (CHO). Anal.Calcd(%) for C6H6INO: C, 30.66;
H, 2.57; N, 5.96. Found: C, 30.96; H, 2.23; N, 5.55.
d
(ppm), 24.2 (CH3); 30.0 (CH2eAr); 39.7 (CH2eN); 81.8 (C-2); 109.6
(C-3); 110.9 (CH, C-7); 118.4 (CH, C-4); 120.7 (CH, C-6); 122.9 (CH, C-5);
134.8(C-3a);141.9(C-7a);170.5 (C]O). Anal. for C12H13IN2O. Calcd:C,
43.92; H, 3.99; N, 8.54. Found: 44.12; H, 4.32; N, 8.22.
Acknowledgements
We thank to the Ministerio de Economia y Competitividad
(Spain) (CTQ2011-29285-C02-01) for financial support.
4.3.9. N-(2-(2-Iodo-5-methoxy-1H-indol-3-yl) ethyl) acetamide
(15).14 Following the general procedure from the melatonin the
iodoemelatonin 15 was obtained as a solid in 98% yield. Mp:
Supplementary data
53e55 ꢀC (hexane/ethyl acetate).1H RMN (CDCl3, 300 MHz)
d (ppm),
Supplementary data related to this article can be found online at
1.93 (s, 3H, CH3); 2.92 (t, J¼6.5 Hz, 2H, CH2eAr); 3.53 (t, J¼6.5 Hz, 2H,
CH2N); 3.84 (s, 3H, OCH3); 5.55 (s, 1H, NH); 6.84 (d, J¼8.8 Hz, 1H, H-
6); 6.96 (s, 1H, H-4); 7.18 (d, J¼8.8 Hz, 1H, H-7); 8.21 (s, 1H, NH). 13C
References and notes
RMN (CDCl3, 75.5 MHz) d (ppm), 22.6 (CH3); 24.5 (CH2); 40.3 (CH2);
55.5 (CH3eO); 59.8 (C-2); 100.6 (CH, C-4); 109.3 (C-3); 111.9 (CH, C-
7); 112.2 (CH, C-6); 122.2 (C, C-3a); 132.8 (CH, C-7a); 154.2 (C-5);
169.6 (C, CO). MS (EI) m/z 359 (MþH); 232 (MHþꢁI).
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Heterocycles 1986, 24, 2879e2885.
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ꢀ
4.3.10. 3-Iodo-1H-pyrrolo[2,3-b]pyridine (16).15 Following the gen-
eral procedure from 7-azaindole the 3-iodo-azaindole 16 was
obtained as a white solid in 65% yield. Mp¼204e205 ꢀC (hexane/
ethyl acetate 6:4) (201e204 ꢀC (methanol))16 1H RMN (CDCl3,
300 MHz)
d
(ppm), 7.20 (dd, J1¼4.8, J2¼7.9 Hz, 1H, H-5); 7.49 (s, 1H,