Solvent-Free Synthesis of Novel Highly Functionalized Dihydroanthra[1,2-b]furan-6,11-dione Derivatives

Abstract

A convenient and environmentally friendly solvent-free procedure has been developed to react 1,5-dihydroxyanthraquinone with dialkyl acetylenedicarboxylates in the presence of triphenylphosphine in one pot to afford novel dialkyl (E)-2-{1,5-dihydroxy-6-[3-methoxy-1-(methoxycarbonyl)-3-oxo-2-(triphenyl-λ ⁵-phosphanylidene)propyl]-9,10-dioxo-9,10-dihydro-2-anthracenyl}-2-butanedioate 3a–c. As a result of intramolecular nucleophilic attack at 90 °C, novel dialkyl (E)-2–{2,7-dihydroxy-3-[2-methoxy-2-oxo-1-(triphenyl-λ ⁵ phosphanylidene)ethyl]-6,11-dioxo-6,11-dihydroanthra[1,2-b]furan-8-yl}-2-butanedioates 4a–c were produced in good yield.

Keywords:

• Acetylenic ester
• C-vinylation
• 1
• 5-dihydroxyanthraquinone
• hydroxyfuran
• solvent free
• triphenylphosphine

Notes

^a λ _abs: maximum absorption wavelength.

^bε: corresponding molar absorption coefficient.

^c λ _em: maximum emission wavelength; maximum excitation wavelength was measured at 230 nm.