Furan Derivatives. V. The Syntheses of 4,5-Dihydro-3<i>H</i>-naphtho[1,8-<i>bc</i>]furans Using Strong Bases
作者:Takaaki Horaguchi、Hidetaka Narita、Tsuneo Suzuki
DOI:10.1246/bcsj.56.184
日期:1983.1
6-methoxy-4,5-dihydro-3H-naphtho[1,8-bc]furan and 6-methoxy-4,5-dihydro-3H-naphtho[1,8-bc]furan-2-carboxylic acid in total yield above 90%. The mechanisms of formation of two products were examined, and potassium 2a-hydroxy-6-methoxy-2a,3,4,5-tetrahydro-2H-naphtho[1,8-bc]furan-2-carboxylate was isolated as a precursor of 6-methoxy-4,5-dihydro-3H-naphtho[1,8-bc]furan. It has become apparent that strong
(4-甲氧基-8-氧代-5,6,7,8-四氢-1-萘氧基)乙酸乙酯和氢氧化钾反应得到6-甲氧基-4,5-二氢-3H-萘基[1 ,8-bc]呋喃和 6-甲氧基-4,5-二氢-3H-萘并[1,8-bc]呋喃-2-羧酸的总产率超过 90%。研究了两种产物的形成机制,并分离出作为前体的 2a-羟基-6-甲氧基-2a,3,4,5-四氢-2H-萘并[1,8-bc]呋喃-2-羧酸钾6-甲氧基-4,5-二氢-3H-萘并[1,8-bc]呋喃。很明显,强碱如氢氧化钠、乙醇钠和氢化钠也可用于合成 6-甲氧基-4,5-二氢-3H-萘并 [1,8-bc] 呋喃衍生物。