反应详情

A solution of 2-bromopyridine (14.4 ml, 150 mmo) in THF (75 ml) was added dropwise to a solution of isopropylmagnesium chloride (75 ml, 2M in THF) at 0° C. under N2, the mixture was then stirred at rt for 3 h, copper Iodide (2.59 g, 13.6 mmol) was added and allowed to stir at rt for another 30 min before a solution of a mixture of E and Z isomers of methyl 2-cyano-2-[6-oxaspiro[4.5]decan-9-ylidene]acetate (16 g, 150 mmol) in THF (60 ml) was added in 30 min. The mixture was then stirred at rt for 18 h. The reaction mixture was poured into a 200 g ice/2 N HCl (100 ml) mixture. The product was extracted with Et2O (3×300 ml), washed with brine (200 ml), dried (Na2SO4) and concentrated. The residual was purified by flash chromatography (100 g silica gel column, eluted by EtOAc in hexane: 3% 2CV; 3-25%, 12 CV; 25-40% 6CV gave methyl 2-cyano-2-[9-(pyridin-2-yl)-6-oxaspiro[4.5]decan-9-yl]acetate (15.44 g, 72% yield, m/z 315.0 [M+H]+ observed) as an amber oil.

1. additionwas added in 30 min
2. stirringThe mixture was then stirred at rt for 18 h
3. extractionThe product was extracted with Et2O (3×300 ml)
4. washwashed with brine (200 ml)
5. dry with materialdried (Na2SO4)
6. concentrationconcentrated
7. customThe residual was purified by flash chromatography (100 g silica gel column
8. washeluted by EtOAc in hexane