Asymmetric Dipyrrin and F-BODIPYs Conjugated to Terminal Alkynes and Alkenes
Carlotta Figliola1, Katherine N Robertson2, Sarah Greening1
1Department of Chemistry, Dalhousie University , Halifax, NS B3H 4R2, Canada.
Abstract:
An asymmetric meso-H dipyrrin featuring a conjugated terminal alkyne substituent was converted to its corresponding difluoro boron complex, and the extent of π-conjugation was extended using Sonogashira cross-coupling. Treatment of the alkyne-substituted dipyrrin with BF3·OEt2 and NEt3 revealed the reactivity of the conjugated terminal alkyne toward Lewis-activated electrophilic substitution and led to the isolation of F-BODIPYs bearing terminal bromovinyl and enol substituents.
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