The Synthesis of Rigid Chromophore–Spacer–Chromophore Dyads and Three-Armed Triads by the 1,3-Dipolar Reaction of Cyclobutene Epoxides with Aromatic Dipolarophiles

Autor: Davor Margetić, Douglas N. Butler, Ronald N. Warrener
Rok vydání: 2013
Předmět:
Zdroj: Synthesis. 45:3413-3425
ISSN: 1437-210X
0039-7881
DOI: 10.1055/s-0033-1340305
Popis: A series of polyaromatic hydrocarbons (PAHs) or their aza derivatives were reacted as dipolarophiles with ring-fused cyclobutene epoxides (CEs) in the 1, 3-dipolar cycloaddition protocol to form 1:1 cycloadducts. The dihydroforms of the PAH chromophores contained in the rigid alicyclic scaffold were dehydrogenated to regenerate the original PAH chromophore and constituted a new route to rigid chromophore-nσ-PAH dyads separated by an alicyclic scaffold. The anthracene 1:1 adduct derived from the reaction with the 5, 8-dimethoxynaphthalene-containing CE was reacted a second time to produce stereoisomeric three-armed triads in which naphthalene chromophores were attached rigidly onto scaffold. Two approaches were used to generate the incipient cyclic 1, 3-dipolar intermediates involved in cycloaddition process. The first method employed ring-opening of functionalised CEs, the other method produced the dipolar reagent in situ by loss of dinitrogen from the initially formed adduct resulting from treatment of fused norbornenes with 2, 5-bis(trifluoromethyl)-1, 3, 4-oxadiazole.
Databáze: OpenAIRE