反应详情

To a stirred mixture of methyl 2-hydroxyimino-2-(thien-2-yl)acetate syn-isomer (3.98 g.) and ethyl vinyl ether (2.5 mls) in ethyl acetate (25 mls) was added phosphorous oxychloride (2 drops). After 20 mins. at 50° the ethyl acetate was washed with saturated sodium bicarbonate solution, dried over sodium sulphate and evaporated to an oil, giving methyl 2-(1 -ethoxy)ethoxyimino-2-(thien-2-yl)acetate (syn-isomer) (5.7 g; 100%) λmax. (EtOH) 289 nm (ε 11,700), τ (CDCl3 ; 60 MHz) 2.61 (multiplet; thienyl H5), 2.82 to 2.97 (multiplet; thienyl H3 and H4), 4.64 (quartet, J 5 Hz; ##STR58## 6.06 (singlet, -COOCH3), 6.24 (quartet, J 7 Hz, OCH2), 8.56 (doublet J 5 Hz; CH-CH3), 8.79 (triplet, J 7 Hz; O.(CH2CH3).

1. washat 50° the ethyl acetate was washed with saturated sodium bicarbonate solution
2. dry with materialdried over sodium sulphate
3. customevaporated to an oil