Synthesis Of Sulfonyl Cyclopentanone Compounds By Radical Rearrangement Cyclization Reaction

Cyclic compounds are widely found in natural products,and these kinds of compounds have good pharmacological activity and physiological activity.They are also the basic structural units of many natural drugs.In particular,the structure of cyclopentanone compounds containing the active groups are widely used in materials chemistry,total synthesis chemistry and pharmaceutical science.Sulfone compounds are a class of functional substances containing sulfonyl groups,and the good biological activity has been valued in the fields of pesticides and pharmaceutical by research workers.Besides,the sulfone compounds can be used as important organic synthesis intermediates,and they have the potential application value in the synthesis field.At the same time,we also found that the synthesis of cyclopentanone compounds modified by sulfonyl suffering from the following problems that less raw materials for preparing them and complicated steps,various byproducts,low yields and harsh reaction conditions.Therefore,the development of simple and efficient synthesis methods have become the focus to many researchers.Mainly due to the mild reaction conditions,strong persistence,low polarity of the solvent and short reaction time,radical rearrangement-cyclization reaction has been much researched by scientists.The main contents are as follows:Part one:A simple and universal synthetic method for the synthesis of 1-(1-enyl)cyclobutanol derivatives is explored.We get the corresponding α-halogenated olefins by using simple olefins as the starting material through the addition-elimination reaction with bromide;then we make the corresponding Grignard reagents and utilize one pot method to synthesize the corresponding 1-(1-enyl)cyclobutanol by adding to the cyclobutanone.The ready availability of starting materials,good applicability and easy-handle protocol make the current methodology efficient for synthesis.Part two:A novel method for the synthesis of sulfonyl cyclopentanone derivates starting with prepared 1-(1-enyl)cyclobutanol and benzenesulfonyl hydrazide derivatives is explored.The system is catalyzed by potassium iodide and TBHP to generate benzenesulfonyl radical,which undergoes radical rearrangement-cyclization strategy to access sulfonyl cyclopentanone derivates.Various functional groups were tolerated well under the reaction conditions.This method make up for the deficiency of the literature reported,and the transition metal-free conditions afforded the environment-friendly approach,which makes this strategy attractive.