Neue Umlagerungen von Aryl-allyl-äthern und Allylphenolen. (Vorläufige Mitteilung)
作者:J. Borgulya、H.-J. Hansen、R. Barner、H. Schmid
DOI:10.1002/hlca.19630460664
日期:——
In position 3 (and 5) substituted phenyl-γ-methyl (and phenyl)-allylethers when subjected to the thermal CLAISEN-rearrangement not only yield the expected o-allyl-phenols but in addition considerable amounts of the P-allylated phenols. Migration to the para-position is favoured by non-polar solvents. This para-migration of the substituted allylgroup is attributed mainly to steric factors. With sterically
在位置3(和5)上,当进行热CLAISEN-重排时,取代的苯基-γ-甲基(和苯基)-烯丙基醚不仅产生预期的邻-烯丙基-酚,而且还产生大量的P-烯丙基化的酚。非极性溶剂有利于迁移至对位。取代的烯丙基的这种对迁移主要归因于空间因素。在位阻的情况下,在邻位或对位烯丙基化苯酚中还发现了烯丙基苯酚的重排:在充分加热至200°时,这些物质转化为热力学更稳定的对位。邻位-烯丙基酚与烯丙基的转化。