substituents interchanged. The facile formation of this unpredictable product is rationalised as proceeding by a retro Diels-Alder reaction of 18 to the tethered 3-methyl-2,4,5-trifluoro-2,4-cyclohexadienylmethyl fluoroketene 24 which has a choice of two intra-molecular recyclisations (by another π4s+π2s Diels-Alder reaction to 25 skeletally identical with 22, and/or a π2s+π2a route to 26) both products reacting
在170°C下真空加热4-甲基-
四氟苯基丙-2-烯基醚16产生的混合物混合物包括3-甲基-2,4,5,7-四
氟三环[3.3.1.0 2,7 ] non-3 -ene-6-one 18,是Claisen重排中间体17的两种可能的分子内Diels-Alder反应之一的产物。提出了第二个分子内Diels–Alder反应的产物22作为形成6-甲基-2,5β,7,7aβ-四
氟-3aβ,4,5,7a-tetrahydroinden-1-的中间体在410°C的闪蒸气相(FVP)热解16中有23个收率低(4%);主要产物是7-甲基-2,5β,6,7aβ-四
氟-3aβ,4,5,7a-四氢
茚-1-酮27(38%)与23相同,但6-Me和7-F取代基互换。可以通过以下方法使这种不可预测的产物的容易形成合理化:通过18的逆Diels-Alder反应与拴系的3-甲基-2,4,5-三
氟-2,4-环
己二烯基甲基
氟乙烯酮