-2(5H)-furanones and 6-substituted 5-iodo-2(2H)-pyranones in which these last compounds are the major products. The 5-iodo-2(2H)-pyranones, which are easily separated chromatographically from the corresponding regioisomers, are able to undergo Stille-type reactions with a variety of organotin compounds to give 5,6-disubstituted 2(2H)-pyranones in moderate to good yields. One of these compounds, i.e
Palladium-catalysed regio- and stereoselective annulation of allenyl stannanes by β-iodo vinylic acids gives the corresponding α-pyrones in high yields. This annulation most probably proceeds through a Stille reaction/cyclisation sequence.
A general route to α-pyrones and 3-substitutedisocoumarins from (Z)-iodovinylic acids 1a−f or 2-iodobenzoic acids 4a−c is described, including compounds bearing a substituent on the aromatic ring. Treatment of (Z)-β-iodovinylic acids 1a−f or 2-iodobenzoic acids 4a−c with various allenyltributyltin reagents in the presence of palladium acetate, triphenylphosphine, and tetrabutylammonium bromide in
Three-component condensation of cyclic 1,3-dicarbonyl compounds, N-phenacylpyridinium salts, and isatins or aromatic aldehydes as a method for the synthesis of novel condensed 2-aroyl-2,3-dihydrofurans
作者:Dmitry V. Osipov、Maxim R. Demidov、Vitaly A. Osyanin、Yury N. Klimochkin
DOI:10.1007/s10593-021-03020-3
日期:2021.10
Three-component condensation of in situ generated pyridinium aroylmethylides with isatins or aromatic aldehydes and cyclic 1,3-dicarbonyl compounds gave a series of condensed 2-aroyl-2,3-dihydrofurans. The reaction proceeds diastereoselectively and represents a cascade process involving the Knoevenagel condensation, the carbo-Michael reaction, and intramolecular nucleophilic substitution. The possibility
The present invention relates to compounds with protected hydroxy groups of formula (I)
1
These compounds are precursors for organoleptic agents, such as fragrances, and masking agents and for antimicrobial agents. When activated, the compounds of formula (I) are cleaved and form one or more organoleptic and/or antimicrobial compounds.