BICYCLO[3.2.1]OCTA-2,6-DIEN-8-YLIDENE (HOMO-7-NORBORNADIENYLIDENE), A “FOILED” CARBENE
作者:Udo H. Brinker、Lothar König
DOI:10.1246/cl.1984.45
日期:1984.1.5
Blcyclo[3.2.1]octa-2,6-dien-8-ylidene nearly exclusively rerranges by 1,2-vinyl migrations. The interaction with the double bond of the six-memberd ring dominates.
Ein effizienter Zugang zu 1,5-Dihydropentalen und 2-Methyl-1,5-dihydropentalen aus Acrolein und Methacrolein
作者:Axel G. Griesbeck
DOI:10.1055/s-1990-26815
日期:——
Acrolein and methacrolein can be converted into 1,5-dihydropentalene and its 2-methyl derivative, respectively, by a simple, three-step process. [4+2]Cycloaddition of the aldehydes with cyclopentadiene affords 5-formyl-2-norbornenes which readily undergo condensation with cyclopentadiene to give 5-(cyclopentadienylidenemethyl)-2-norbornenes. These protected 6-vinylpentafulvenes undergo retro-cleave to cyclopentadiene and the 1,5-dihydropentalenes on vacuum flash thermolysis.