反应详情

A solution of ethyl 3,4,5-trimethoxybenzylcyanoacetate (14.7g) in triethyl orthoformate (100 ml) was heated at reflux for 18 hours using a steam-jacketed column for continuous removal of ethanol. The solution was cooled, and most of the excess orthoformate was removed in vacuo. The crystals obtained were washed with ether and dried to yield colourless crystals of α-carbethoxy-α-diethoxymethyl-β-(3,4,5-trimethoxy phenyl)propionitrile (16.3 g, 82%), m.p. 91θ ; nmr (CDCl3) δ1.13, 1.20. and 1.32 (triplets, 9, CH3CH2O-), 3.15 (s, 2, Ar-CH2 -C), 3.4-4.0 (m, 4, m, 4, CH3CH2 -O), 3.85 (s, 9, -C6H2 -(OCH3)3), 4.13 (q, 2, CH3CH2 -OCO), 4.80 (s, 1, -CH (OEt)2), and 6.55 (s, 2, aromatic H). Anal. Calcd. for C20H29NO7 : C, 60.74; H, 7.39; N, 3.54. Found: C, 60.56; H, 7.33; N, 3.64.

1. temperatureat reflux for 18 hours
2. customfor continuous removal of ethanol
3. temperatureThe solution was cooled
4. custommost of the excess orthoformate was removed in vacuo
5. customThe crystals obtained
6. washwere washed with ether
7. customdried