Methyl 2-(4′-hydroxybutyl)chromone-3-carboxylate (7) and the derived epoxide (13) undergo spirocyclisation on treatment with iodomethane–potassium carbonate and Lewis acid respectively.
Reaction of chromones with hydroxylamine in anhydrous methanol
作者:Vince Szabó、János Borbély、Edit Theisz、Sándor Nagy
DOI:10.1016/s0040-4020(01)87646-8
日期:1986.1
The reaction of 4H-1-benzopyran-4-one (chromone, ,) and its substituted derivatives with hydroxylamine in aqueous alcohols gives isoxazoles and , as the major products, whereas is transformed mainly into with hydroxylamine hydrochloride in anhydrous methanol, compounds , and can be also isolated, and the formation of and has been detected, as well. Depending on the character of the substituent, substituted
Chemistry of aldolate dianions. β-Silyloxy silyl enol ethers as bifunctional nucleophilic equivalents for oxygen heterocycle synthesis
作者:Van A. Martin、Françoise Perron、Kim F. Albizati
DOI:10.1016/s0040-4039(00)94538-6
日期:1990.1
Heteroannulation of 4-oxo-4H-1-benzopyrans (chromones) via the conjugate addition of haloalkanols in the presence of base
作者:Peter J. Cremins、Roy Hayes、Timothy W. Wallace
DOI:10.1016/s0040-4020(01)80889-9
日期:1991.11
Chromones (4-oxo-4H-1-benzopyrans) bearing electron-withdrawing substituents at C-3 react with 2-haloethanols and potassium carbonate in acetone to produce tetrahydrofuro[2,3-b][1]benzopyran-4-ones, the heteroannulation proceeding via the conjugate addition of the haloethanol to the chromone, followed by intramolecular alkylation. Under the conditions of the reaction, the products derived from chromone-3-carbaldehydes undergo in situ deformylation.
MARTIN, VAN A.;PERRON, FRANCOISE;ALBIZATI, KIM F., TETRAHEDRON LETT., 31,(1990) N, C. 301-304
作者:MARTIN, VAN A.、PERRON, FRANCOISE、ALBIZATI, KIM F.