Tributyltin Chloride → (2R)-2-methyl-1-{2-[5-(tributylstannyl)-1-benzofuran-2-yl]ethyl}pyrrolidine
Reaction equation
Br[C:2]1[CH:3]=[CH:4][C:5]2[O:9][C:8]([CH2:10][CH2:11][N:12]3[CH2:16][CH2:15][CH2:14][C@H:13]3[CH3:17])=[CH:7][C:6]=2[CH:18]=1.C([Li])(C)(C)C.[CH2:24]([Sn:28](Cl)([CH2:33][CH2:34][CH2:35][CH3:36])[CH2:29][CH2:30][CH2:31][CH3:32])[CH2:25][CH2:26][CH3:27]>>[CH3:17][C@@H:13]1[CH2:14][CH2:15][CH2:16][N:12]1[CH2:11][CH2:10][C:8]1[O:9][C:5]2[CH:4]=[CH:3][C:2]([Sn:28]([CH2:29][CH2:30][CH2:31][CH3:32])([CH2:33][CH2:34][CH2:35][CH3:36])[CH2:24][CH2:25][CH2:26][CH3:27])=[CH:18][C:6]=2[CH:7]=1Participants
Procedure
As shown in Scheme 13, (2R)-1-[2-(5-bromo-1-benzofuran-2-yl)ethyl]-2-methylpyrrolidine is treated with tert-butyl lithium and tributylstannyl chloride at −78° C. to provide (2R)-2-methyl-1-{2-[5-(tributylstannyl)-1-benzofuran-2-yl]ethyl}pyrrolidine. (2R)-2-Methyl-1-{2-[5-(tributylstannyl)-1-benzofuran-2-yl]ethyl}pyrrolidine is treated with a suitable starting material, for example, aryl halides, aryl triflates, or heterocyclic halides in the presence of a palladium catalyst, like palladium (II) acetate, and a trivalent phosphine, like tri(2-furyl)phosphine, in an organic solvent such as dimethylformamide at 25° C. to 120° C. to provide compounds of formula (50). Compounds of formula (50) can be isolated and purified by methods known to those skilled in the art. For example, compounds of formula (50) can be partitioned between dichloromethane and water, the organic phase concentrated, and the residue purified by chromatography on silica gel.
Sources & evidence
- ORD record
- ord-93445a32ff914d1cb5b31365b46f2251
- Source dataset
- uspto-grants-2009_05
- Patent number
- US07538138B2
Reaction notes
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