Isocyanide-based Multicomponent Reactions And Some Related Cycloaddition Reactions

The exceptional reactivity of the functional group of isocyanide provides apowerful driving force and broad space for development of related multicomponentreactions. Accordingly, isocyanides-based multicomponent reactions (IMCRs) haveattracted enormous attention from organic chemists. In this thesis, we mainly focusour attention on isocyanide based multicomponent reactions and related cycloadditionreaction. The thesis consists of the following contents:Part1, researches on three-component cascade cycloaddition of isocyanide,-substituted allenoate, and methyleneindolinone.Multicomponent reaction of isocyanide,-substituted allenoate andmethyleneindolinone can provide functionalized polycyclic compounds in a highlyefficient manner under mild reaction conditions. The [1,5]-H shift is believed to be thekey step in the above transformation. This process exhibits excellent regioselectivity,stereoselectivity and good yields without the addition of any catalyst. This methodalso shows excellent substrate generality, which is very significant for the fast andefficient construction of corresponding compound library. Remarkably, the ethoxygroup of the cycloadduct can be easily replaced by other alkyl group in acidiccondition in the presence of excessive alcohols. A very interesting oxindolescompound is also obtained in acidic conditions with other solvents.Part2, researches on cascade cycloaddition of methyleneindolinone andisocyanide.In the presence of catalytic amount of BF3·Et2O, cascade cycloadditions ofisocyanides and methyleneindolinone proceed smoothly to generate functionalizedquinoline. The present transformation involves the ring-opening ofmethyleneindolinone and the construction of two other new rings simultaneously. Thismethod has excellent substrate suitability, atom economy and convenient experientalset-up. These advantages make this protocol be efficient route to synthesizefunctionalized quinoline.