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Abstract
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There are many studies on the reaction between trivalent phosphorus nucleophiles and acetylenic esters in the presence of OH, NH, or CH acids. In some cases ylide products are stable, but in other cases they can not be isolated and appear to occure as an intermediate on the pathway to an observed product. In many cases this reaction carried out in dry organic solvents such as dry dichloromethane or diethyl ether. In this work we wish to report the three component reaction of strong C-H acids such as cyclic or acyclic 1,3-diketones and acetylenic esters in the presence of triphenylphosphine to produced highly functionalized stable phosphoruse ylieds or chromene derivatives in THF/H2O (1:1) in good yields. From the reaction of alkyl propiolates with acetylenic esters in the presence of cyclic 1,3-diketones such as 5,5-dimethyl-1,3-cyclohexanedione or 1,3-cyclohexanedione, stable 1,4-dionic compounds are obtained in good yields. This methodology is of interest because the use of water as solvent and reduced the time of reaction, thus minimizing the cost, operational hazards and environmental pollution.
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