Michael Addition and Diels-Alder Reactions on Some Carbonyl Compounds

Abstract

This thesis is divided into two parts, the first one concerned with the study of the reactions of 2-propen-1-one derivatives under Michael conditions. The second part aims to develop a new methodology for the synthesis of pancratistatin by studying the behaviour of 2-(1,3-butadien-1-yl)benzoyl­ oxazolone derivative towards intramolecular Diels-Alder reaction

The First part:

The aim of this part was to continue the study of the chemical behaviour and the relative activity of 1,3-diaryl-2- propen-1-one derives towards the nucleophilic reagents, and comparing the results with those which abstained by other scientific authors.

Thus, when the compounds 3-aryl-1-(2,4-dimethoxy­ phenyl)-2-propen-1-one (I) were reacted with 1,3-diphenyl pyrazolin-5-one (lla) in the presence of piperidine as a catalytic base, 4-aryl-bis-1,3-diphenylpyrazolo[5,4-b]4H-pyrane (ill) and 1- (2,4-dimethoxyphenyl)-3-(p-substitutedphenyl)-3-(1,3-diphenyl- 5-oxopyrazolin-4-yl)propan-1-one (IV) were obtained. Alkaline hydrolysis of ill afforded bis-(3-Substituted-1-phenyl-5-oxo­ pyrazolin-4-yl) arylrnethane (V). On studying the behaviour of the normal Michael adducts IV towards the nitrogen nucleophilic reagents such as thiourea, hydroxyl-amine, hydrazine hydrate, and,also, with·acetic anhydride , N-thio carbarnido-3-aryl-1-(2,4-dimethoxyphenyl)-3-(1-phenyl-3- substituted-5-oxo-pyrazolin-4-yl)propan-1-one imine (VI),3- ary1-1-(2,4-dimethoxy-pheny1)-3-(1-pheny1-3-substituted-5-oxo­ pyrazolin-4-yl)propan-1-one oxime (VII),3-aryl-1-(2,4-dimeth-