Study On The Approach To Synthesize 2-Oxazolin-4-ones And1,3-Oxazin-4-ones

Heterocyclic compounds and their derivatives are important intermediates in biological engineering,food flavoring,pharmaceutical synthesis and dyes,a lot of attentions have also been paid by researchers for its structure particularity and potential pharmacological activity.So numerous impressive synthetic methodologies for the construction of spirooxindole derivatives have been recorded over the past years.Thus,it is a profound progress to fabricate heterocyclic compounds with innovative structure and function using a simple and efficient synthetic method.In this thesis,five-membered heterocyclics 2'-(dialkylamino)-1-alkyl-4'H – spiro[indoline-3,5'-oxazole]-2,4'-diones and six-membered heterocyclics 2-(dialkylamino)-5,6-dihydro-4H-naphtho[2,1-e][1,3]oxazin-4-ones were constructed using Vilsmeier salts and ?-hydroxy substituted,?-carbonyl substituted amides.The specific work is as follows:The spirooxindole unit is present in a large number of natural products as well as pharmaceutically important molecules,and have certain physiological activities and potential drug activities.So we use 3-hydroxy-2-oxoindole-3-carboxamide(?-hydroxy substituted amide)and Vilsmeier salts as substrates,by reacting solvents,reaction temperature,type of bases,ratio of reactants and materials,etc.A series of reaction conditions were selected for the simple and efficient synthesis of a five-membered heterocyclic 2'-(dialkylamino)-1-alkyl-4'H-spiro[indoli ne-3,5'-oxazole.The yield of 2,4'-diketone compounds is up to 97%.This kind of compounds are likely to provide a new idea for the development of new drugs.Compared with?-hydroxy amides,?-carbonyl amide are possible suitable substrates for similar transformation due to keto-enol tautomerism property of ?-carbonyl amides.So we designed and synthesized a potential nucleophilic compound1-oxo-1,2,3,4–tetrahydronapht halene-2-carboxamide(?-carbonyl amide)and Vilsmeier salts are substrates,by reaction solvent,reaction temperature,type of bases,reaction Screening of a series of reaction conditions,we selected a simple and efficient synthesis of six-membered heterocyclic 2-(dialkylamino)-5,6-dihydro-4H-naphtho[2,1-E] [1,3] Oxazine-4-one,the yield is as high as 86%.