Electric Literature of 1632-83-3,Some common heterocyclic compound, 1632-83-3, name is 1-Methylbenzimidazole, molecular formula is C8H8N2, traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.
General procedure: The product 7h is a representative reaction. To a screw-cappedvial (5 mL) containing Ni(COD)2 (14 mg, 0.05 mmol), IMes (14 mg, 0.05 mmol),benzimidazole (66 mg, 0.50 mmol), and potassium tert-butoxide (5.6 mg, 0.05 mmol)was added toluene (1.0 mL) followed by the addition of 1,5-cyclooctadiene (43 mg,0.04 mmol) in a glove box atmosphere. The reaction vial was closed and heated at 80o C for 2 hours outside of the glove box. The resulting mixture was filtered throughCelite and washed with dichloromethane. The filtrate solution was concentrated invacuo to afford the crude product, which was further purified by columnchromatography using hexane/ethyl acetate (4:1 v/v) as eluent to furnish(E)-2-(cyclooctenyl)-1-methyl-benzimidazole 7h (117 mg) in 97% yield.The compound 7i was synthesized via similar conditions (see Table 3)._(E)-2-(cyclooct-1-en-1-yl)-1-methyl-1H-benzo[d]imidazole (7h): 1H NMR (300MHz, CDCl3): delta 7.75-7.71 (m, 1H), 7.25-7.19 (m, 3H), 6.06 (t, J = 8.1, 1H), 3.72 (s,3H), 2.75-2.71 (m, 2H), 2.36 (dd, J = 8.1, 11.4, 2H), 1.66-1.59 (m, 8H). 13C NMR (75MHz, CDCl3): delta 155.6, 142.4, 136.1, 135.8, 131.6, 122.1, 121.8, 119.3, 109.2, 31.6,29.3, 29.0, 28.9, 26.9, 26.4, 26.1. HR-MS (EI): calculated for: [C16H20N2]+: 240.1626.Found: 240.1620.
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 1-Methylbenzimidazole, its application will become more common.
Reference:
Article; Lee, Wei-Chih; Shih, Wei-Chin; Wang, Ting-Hsuan; Liu, Yuhua; Yap, Glenn P.A.; Ong, Tiow-Gan; Tetrahedron; vol. 71; 26-27; (2015); p. 4460 – 4464;,
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem