[Cl-].[CH3:2][O:3][CH2:4][P+](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1.[Li]CCCC.[Cl:29][C:30]1[CH:35]=[CH:34][N:33]=[C:32]([C:36]([CH:38]2[CH2:40][CH2:39]2)=O)[C:31]=1[O:41][CH3:42]>C1COCC1>[Cl:29][C:30]1[CH:35]=[CH:34][N:33]=[C:32]([C:36]([CH:38]2[CH2:40][CH2:39]2)=[CH:2][O:3][CH3:4])[C:31]=1[O:41][CH3:42](Methoxymethyl)triphenylphosphonium chloride (1.6 g, 4.7 mmol) was dissolved in THF (20 ml) and cooled to −30° C. 2.5 Molar n-BuLi in hexanes (1.89 ml, 4.7 mmol) was and the mixture stirred for 1 h. (4-chloro-3-methoxypyridin-2-yl)-(cyclopropyl)methanone (500 mg, 2.4 mmol) dissolved in THF (5 ml) was added slowly and stirred for 4 h. The reaction mixture was quenched with saturated ammonium chloride (20 mL) and stirred overnight. 25 mL ethyl acetate was added and the layers partitioned. The organic phase was dried over sodium sulfate, filtered and evaporated to dryness to obtain crude product which was purified over silica gel using 0:1 to 3:7 ethyl acetate in heptane to obtain 4-chloro-2-(1-cyclopropyl-2-methoxyvinyl)-3-methoxy-pyridine as a clear oil (361 mg, 63%).
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