Compound 2g. Mp 166–168 ЊC; νmax(KBr)/cmϪ1 3380, 3240,
Table 2 Selected bond lengths (Å) and angles (Њ)
2210, 1675, 1620 and 1510; δH 4.26 (1H, d, J 8.8, ArCH), 4.43
(1H, d, J 8.8, ArCH), 5.27 (2H, br s, NH2), 5.98 (4H, s,
2 × OCH2O), 6.30–6.93 (6H, m, 2 × ArH); m/z 399 (M ϩ 1,
15.4%), 398 (Mϩ, 100), 371 (16.5), 155 (43.5), 154 (26.7)
(Found: C, 66.52; H, 3.78; N, 13.82. C22H14N4O4 requires C,
66.33; H, 3.54; N, 14.06%).
Cl1᎐C12
Cl2᎐C18
N1᎐C6
N2᎐C2
N3᎐C7
N4᎐C8
C1᎐C2
C1᎐C5
C1᎐C6
C2᎐C3
C3᎐C4
C3᎐C7
C3᎐C8
C4᎐C5
1.752(6)
1.757(6)
1.141(8)
1.338(7)
1.133(7)
1.137(7)
1.332(7)
1.514(8)
1.436(9)
1.539(8)
1.570(7)
1.472(8)
1.470(8)
1.531(7)
C2᎐C1᎐C6
C5᎐C1᎐C6
N2᎐C2᎐C1
N2᎐C2᎐C3
C1᎐C2᎐C3
C2᎐C3᎐C4
C2᎐C3᎐C7
C2᎐C3᎐C8
C4᎐C3᎐C7
C4᎐C3᎐C8
C7᎐C3᎐C8
C3᎐C4᎐C5
C1᎐C5᎐C4
N1᎐C6᎐C1
N3᎐C7᎐C3
N4᎐C8᎐C3
123.2(5)
122.5(5)
133.1(6)
118.9(5)
108.1(5)
101.4(4)
114.7(4)
107.8(5)
112.3(4)
111.7(4)
108.9(4)
103.1(4)
100.2(4)
178.8(7)
176.9(6)
177.3(7)
Compound 2h. Mp 125–127 ЊC; νmax(KBr)/cmϪ1 3360, 3240,
2210, 1680, 1630 and 1510; δH 4.23 (1H, d, J 9.0, ArCH), 4.60
(1H, d, J 9.0, ArCH), 5.61 (2H, br s, NH2), 6.23–7.53 (6H, m,
2 × furan-H); m/z 291 (M ϩ 1, 21.3%), 290 (Mϩ, 100), 263
(15.5), 155 (37.4) (Found: C, 66.43; H, 3.61; N, 19.41.
C16H10N4O2 requires C, 66.20; H, 3.47; N, 19.30%).
Compound 2i. Mp 138–140 ЊC; νmax(KBr)/cmϪ1 3360, 3220,
2220, 1670, 1620 and 1525; δH 3.74 (1H, d, J 9.5, ArCH), 3.80
(6H, s, 2 × OCH3), 3.88 (6H, s, 2 × OCH3), 4.48 (1H, d, J 9.5,
ArCH), 5.40 (2H, br s, NH2), 6.60–7.15 (6H, m, 2 × ArH);
m/z 431 (M ϩ 1, 15.2%), 430 (Mϩ, 100), 403 (25.7), 293 (21.3),
266 (19.3), 156 (18.4), 155 (13.2) (Found: C, 67.21; H, 5.01;
N, 13.20. C24H22N4O4 requires C, 66.97; H, 5.15; N, 13.02%).
C2᎐C1᎐C5
114.1(5)
refinement gave final R = 0.082 and Rw = 0.098 with w = 1/
σ2(F0), S = 2.81. The maximum peak in the final difference
General procedure for the intramolecular reductive cyclization
reactions
Fourier map is 0.42 e ÅϪ3 and the minimum peak is Ϫ0.52 e ÅϪ3
.
In the final circle refinement the largest parameter shift (∆/σ)max
is 0.04. All calculations were performed using the TEXSAN
program package.15 Selected bond lengths and angles are shown
in Table 2.‡
A solution of nitro cyano olefins 3 (1 mmol) in anhydrous
THF (3 ml) was added to a solution of SmI2 (6 mmol) in THF
(40 ml) at room temperature under a dry nitrogen atmosphere.
The mixture was stirred under these conditions until the
reaction was complete. The reaction mixture was poured into
10% aqueous K2CO3 (50 ml) and extracted with diethyl ether
(4 × 30 ml). After usual work-up, the crude product was
purified by preparative thin layer chromatography [eluent, ethyl
acetate–cyclohexane (1:1)].
Compound 2b. Mp 95–97 ЊC; νmax(KBr)/cmϪ1 3380, 3240,
2210, 1670, 1620 and 1520; δH 3.68 (3H, s, OCH3), 3.74 (3H, s,
OCH3), 4.17 (1H, d, J 9.5, ArCH), 4.50 (1H, d, J 9.5, ArCH),
5.40 (2H, br s, NH2), 6.70–7.48 (8H, m, 2 × ArH); m/z 371
(M ϩ 1, 30.3%), 370 (Mϩ, 100), 369 (35.2), 355 (21.3), 339 (35),
225 (16.4), 199 (31.7), 184 (32.5), 171 (68.6), 155 (50.4), 142
(31.4), 114 (35.5) (Found: C, 71.62; H, 4.71; N, 15.30.
C22H18N4O2 requires C, 71.34; H, 4.90; N, 15.13%).
Compound 4a. Mp 226–227 ЊC; νmax(KBr)/cmϪ1 3400, 3160
and 2230; δH 5.46 (2H, br s, NH2), 7.32–7.71 (4H, m, ArH),
8.30 (1H, s, hetero-ArH); m/z 170 (M ϩ 1, 21.5%), 169 (Mϩ,
100), 144 (73.2), 143 (33.5), 117 (20.3), 116 (32.5) (Found: C,
70.86; H, 4.36; N, 24.78. C10H7N3 requires C, 70.99; H, 4.14;
N, 24.84%).
Compound 2c. Mp 190–192 ЊC; νmax(KBr)/cmϪ1 3375, 3240,
2210, 1670, 1620 and 1520; δH 2.23 (3H, s, CH3), 2.30 (3H, s,
CH3), 3.77 (1H, d, J 9.5, ArCH), 4.51 (1H, d, J 9.5, ArCH),
5.35 (2H, br s, NH2), 6.95–7.35 (8H, m, 2 × ArH); m/z 339
(M ϩ 1, 15.1%), 338 (Mϩ, 100), 325 (15.6), 324 (28.8), 155 (15),
91 (10.4) (Found: C, 77.97; H, 5.21; N, 16.73. C22H18N4 requires
C, 78.08; H, 5.36; N, 16.56%).
Compound 4b. Mp 280 ЊC (decomp.); νmax(KBr)/cmϪ1 3400,
3160 and 2230; δH 6.14 (2H, s, OCH2O), 6.66 (2H, br s, NH2),
6.91 (1H, s, ArH), 7.12 (1H, s, ArH), 8.37 (1H, s, hetero-ArH)
(Found: C, 62.21; H, 3.15; N, 19.50. C11H7N3O2 requires C,
61.97; H, 3.31; N, 19.71%).
Compound 2d. Mp 145–147 ЊC; νmax(KBr)/cmϪ1 3380, 3215,
2210, 1680, 1630 and 1500; δH 3.70 (1H, d, J 9.0, ArCH), 4.54
(1H, d, J 9.0, ArCH), 5.41 (2, br s, NH2), 6.97–7.63 (8H, m,
2 × ArH); m/z 470 (M ϩ 4, 48.3%), 468 (M ϩ 2, 100), 466 (Mϩ,
51.3), 391 (23.1), 390 (36.5), 389 (74.2), 388 (30.4), 309 (35.2),
308 (47.1), 155 (43.9) (Found: C, 51.49; H, 2.77; N, 11.70.
C20H12Br2N4 requires C, 51.31; H, 2.58; N, 11.97%).
Acknowledgements
We are grateful to the National Natural Science Foundation
of China (Project No. 294938004 and 29672007) and the
Laboratory of Organometallic Chemistry, Shanghai Institute
of Organic Chemistry, Chinese Academy of Science for
financial support. We thank Professor Weimin Lu for helpful
discussions about the X-ray analysis for compound 2a.
Compound 2e. Mp 116–118 ЊC; νmax(KBr)/cmϪ1 3380, 3210,
2210, 1670, 1630, 1600 and 1580; δH 3.60 (1H, d, J 9.2, ArCH),
4.50 (1H, d, J 9.2, ArCH), 5.33 (2H, br s, NH2), 6.78–7.60 (8H,
m, 2 × ArH); m/z 470 (M ϩ 4, 46.2%), 468 (M ϩ 2, 100), 466
(Mϩ, 50.3), 390 (20.3), 389 (49.1), 388 (32.6), 308 (27.3), 155
(15.4), 154 (41.7) (Found: C, 51.61; H, 2.31; N, 12.26.
C20H12Br2N4 requires C, 51.31; H, 2.58; N, 11.97%).
References
Compound 2f. Mp 128–130 ЊC; νmax(KBr)/cmϪ1 3380, 3200,
2210, 1670, 1630 and 1505; δH 3.80 (1H, d, J 9.2, ArCH),
4.58 (1H, d, J 9.2, ArCH), 5.20 (2H, br s, NH2), 7.10–7.70 (10H,
m, 2 × ArH); m/z 311 (M ϩ 1, 21.5%), 310 (Mϩ, 100), 283
(15.3), 156 (15.1), 155 (41.4), 128 (18.4) (Found: C, 77.57;
H, 4.38; N, 18.20. C20H14N4 requires C, 77.40; H, 4.55; N,
18.05%).
1 P. Girard, J. L. Namy and H. B. Kagan, J. Am. Chem. Soc., 1980,
102, 2693.
2 For reviews see: G. A. Molander and C. R. Harris, Chem. Rev.,
1996, 96, 307; F. Matsuda, Synth. Org. Chem. Jpn., 1995, 53,
987; G. A. Molander, Org. React., 1994, 46, 221; T. Imamota,
Lanthanides in Organic Synthesis, Academic Press, London, 1994,
ch. 4; M. Shibasaki and H. Sasai, Synth. Org. Chem. Jpn., 1993,
51, 972; G. A. Molander, Chem. Rev., 1992, 92, 29; D. P. Curran,
T. L. Fevig, C. P. Jasperse and M. J. Totleben, Synlett, 1992, 943;
J. A. Soderquist, Aldrichim. Acta, 1991, 24, 15; G. A. Molander,
Comprehensive Organic Synthesis, eds. B. M. Trost and I. Fleming,
Pergamon, Oxford, vol. 1, 1991, 251; H. B. Kagan, New. J. Chem.,
1990, 14, 453; G. A. Molander, in Chemistry of the Metal-Carbon
Bond, ed. F. R. Hartly, Wiley, Chichester, 1989, vol. 5, ch. 8;
H. B. Kagan, M. Sasaki and J. Collin, Pure Appl. Chem., 1988,
60, 1725; H. B. Kagan and J. L. Namy, Tetrahedron, 1986, 42,
6573.
‡ Full crystallographic details, excluding structure factor tables, have
been deposited at the Cambridge Crystallographic Data Centre
(CCDC). For details of the deposition scheme, see ‘Instructions for
Authors’, J. Chem. Soc., Perkin Trans. 1, available via the RSC Web
material should quote the full literature citation and the reference
number 207/234.
J. Chem. Soc., Perkin Trans. 1, 1998
2401