| 17323395 |
Chang HT, Jeganmohan M, Cheng CH: Highly efficient cyclization of o-iodobenzoates with aldehydes catalyzed by cobalt bidentate phosphine complexes: a novel entry to chiral phthalides. Chemistry. 2007;13(15):4356-63.
Methyl 2-iodobenzoates 1 a-c undergo cyclization reactions with various aromatic aldehydes 2 a-m (RC6H4CHO: R=H 2 a, 4-CH3 2 b, 4-tBu 2 c, 4-OMe 2 d, 3-OMe 2 e, 4-Cl 2 f, 4-CF3 2 g, 4-CN 2 h, 4-Ph 2 i; benzo [d][1,3] dioxole-5-carbaldehyde (2 j), 1-napthaldehyde (2 k), benzofuran-2-carbaldehyde (2 l), and isonicotinaldehyde (2 m)) in the presence of [CoI2 (dppe)] (dppe=1,2-bis (diphenylphosphino) ethane) and Zn powder in dry THF at 75 degrees C for 24 h to give the corresponding phthalide derivatives 3 a-m and 3 q-t in good to excellent yields. |
31(0,1,1,1) |
Details |