作者:E. Schmid、Gy. Fráter、H.-J. Hansen、H. Schmid
DOI:10.1002/hlca.19720550526
日期:1972.7.10
2-(1′-Arylallyl)-phenols (9, 10, 11, 12, 13, 14, 15, 16) are transformed on heating in N, N-diethylaniline at 225° into trans-2-aryl-3-methyl-coumarans (26, 29, 32, 34, 36, 38, 40, 42) in excellent yields. The corresponding cis-coumarans are minor products. Similar thermal behaviour is shown by 2-(1′-vinylallyl)-phenols (7, 8) which are thermally converted into trans-3-methyl-2-vinyl-coumarans (24
2-(1'- Arylallyl)-phenols(9,10,11,12,13,14,15,16)在225℃被变换对n个加热,N-二乙基苯胺为反式-2-芳基-3-甲基-coumarans(26,29,32,34,36,38,40,42)以优良产率。相应的顺式香豆素是次要产品。相似的热行为是由2-(1'- vinylallyl)-phenols(示出7,8),其被热转化成反式-3-甲基-2-乙烯基- coumarans(24,19)和5-甲基-2,5-二氢- (1-benzoxepins)(25,18)。后者的化合物是热不稳定的,并重新排列,得到近似3:1分的混合物的反式-和顺式-3-甲基-2-乙烯基- coumarans(24,19)。方案2、3和4中讨论了这些新的热重排的反应机理。