Microwave-assisted synthesis of substituted imidazoles on a solid support under solvent-free conditions

(a) Caddick, S. Tetrahedron 1995, 51, 10403–10432. (b) Strauss, C. R.; Trainor, R. W. Aust. J. Chem. 1995, 48, 1665–1692. Cotterill, I. C.; Usyatinsky, A. Ya.; Arnold, J. M.; Clark, D. S.; Dordick, J. S.; Michels, P. C.; Khmelnitsky, Yu. L. Tetrahedron Lett. 1998, 39, 1117–1120. Krieg, B.; Manecke, G. Z. Naturforsch. 1967, 22b, 132–141. Sarshar, S.; Siev, D.; Mjalli, M. M. Tetrahedron Lett. 1996, 37, 835–838. (a) Reddy, A. C. S.; Rao, P. S.; Venkataratham, R. V. Tetrahedron 1997, 53, 5847–5854. (b) Bougrin, K.; Soufaoui, M. Tetrahedron Lett. 1995, 36, 3683–3686. (c) Ben-Alloum, A.; Bakkas, S.; Soufaoui, M. Tetrahedron Lett. 1998, 39, 4481–4484. (d) Glas, H.; Thiel, W. R. Tetrahedron Lett. 1998, 39, 5509–5510. (e) Martin-Aranda, R. M.; Vicente-Rodriguez, M. A.; Lopez-Pestana, J. M.; Lopez-Peinado, A. J.; Jerez, A.; Lopez-Gonzales, J. D.; Banares-Munoz, M. A. J. Mol. Catal. A 1997, 124, 115–121. (f) Bogdal, D.; Pielichowski, J.; Jaskot, K. Heterocycles 1997, 45, 715–722. In the original procedure the reaction is performed in refluxing acetic acid.3 Compound 1b: 1H NMR (DMSO-d6, 360 MHz) δ (7.15, m, 2H), (7.29–7.51, m, 10H), (7.68, dd, 1H), (12.83, s, 1H). HRMS [M+H]+=303; compound 1d: 1H NMR (CD3OD, 360 MHz) δ (2.34, s, 6H), (7.13, m, 5H), (7.33, d, 4H), (7.45, d, 1H), (7.65, d, 1H). HRMS [M+H]+=331; compound 2a: 1H NMR (DMSO-d6, 360 MHz) δ (2.53, t, 2H), (4.08, t, 2H), (6.66, m, 2H), (7.14–7.53, m, 15H), (7.66, d, 2H), (8.09, d, 1H). 13C NMR (DMSO-d6, 90 MHz) δ 36.6, 45.4, 125.2, 126.0, 128.0, 128.2, 128.4, 128.6, 128.7, 129.1, 130.2, 134.6, 136.5, 145.3, 146.7. HRMS [M+H]+=401; compound 2b: 1H NMR (DMSO-d6, 360 MHz) δ (2.74, t, 2H), (4.17, t, 2H), (6.80, d, 2H), (7.20, m, 6H), (7.40, m, 5H), (7.55, m, 4H), (7.74, d, 1H). 13C NMR (DMSO-d6, 90 MHz) δ 35.5, 45.7, 125.9, 126.3, 126.6, 127.4, 128.1, 128.3, 128.5, 129.1, 130.2, 130.4, 131.0, 132.8, 134.2, 136.6, 140.6. HRMS [M+H]+=407; compound 2c: 1H NMR (DMSO-d6, 360 MHz) δ (2.23, s, 3H), (2.42, s, 3H), (2.51, t, 2H), (4.08, t, 2H), (6.67, m, 2H), (7.12, d, 2H), (7.14–7.52, m, 16H), (7.63, d, 1H), (8.07, d, 1H). 13C NMR (DMSO-d6, 90 MHz) δ 20.6, 20.9, 35.6, 45.7, 125.1, 126.0, 126.6, 128.0, 128.2, 128.4, 128.5, 128.6, 129.2, 130.7, 131.3, 131.9, 135.1, 136.5, 137.3, 138.1, 146.5. HRMS [M+H]+=429; compound 2d: 1H NMR (CD3OD, 360 MHz) δ (1.25, t, 3H), (2.70, q, 2H), (5.14, s, 2H) (6.64, s, 1H), (7.12–7.55, m, 15H), (7.90, d, 1H). 13C NMR (DMSO-d6, 90 MHz) δ 15.3, 27.9, 47.2, 124.3, 125.2, 126.0, 127.9, 128.4, 129.0, 130.4, 130.6, 133.0, 134.4, 139.7, 143.8, 144.7, 145.6, 147.2. HRMS [M+H]+=449.