反応 #59131

反応方程式

cis-2-(4-bromobenzoyl)-1-cyclohexanecarboxylic acid

2,2-dimethoxypropane

HCl

→

methyl cis-2-(4-bromobenzoyl)cyclohexane-carboxylate

収率 42.1%

溶媒

MeOH

反応条件

後処理

1. 1
   その他evaporated to dryness
2. 2
   その他The resulting residue was purified by flash chromatography (Biotage Flash 40M)

実験手順

To a solution of cis-2-(4-bromobenzoyl)-1-cyclohexanecarboxylic acid (4.0 g, 12.85 mmol) in MeOH (50 mL) was added 2,2-dimethoxypropane (2.01 g, 19.28 mmol) and HCl (4.0 M in dioxane, 1.20 mL). The resulting solution was stirred at 40° C. for 3 days, and then evaporated to dryness. The resulting residue was purified by flash chromatography (Biotage Flash 40M) using 3 to 6% ethyl acetate in hexanes to afford methyl cis-2-(4-bromobenzoyl)cyclohexane-carboxylate (1.76 g, 42%). LC-MS ret. time 3.40; m/z 326 (MH+); 1H NMR (400 MHz, CD2Cl2) δ 1.35-1.51 (m, 3H), 1.72-1.86 (m, 2H), 1.91-2.05 (m, 2H), 2.11-2.20 (m, 1H), 2.74 (m, 1H), 3.58 (s, 3H), 3.82 (q, 1H), 7.62 (m, 2H), 7.73 (m, 2H).

出典