Studies On Copper-catalyzed Addition Of Several Types Of Nucleophiles To Cyclopropylene

Cyclopropene is the smallest unsaturated carbocycle.Its high strain energy can result in very high chemical reactivity.There is a rich diversity of cyclopropene chemistry under transition-metal catalysis;however,Cu-catalyzed reactions of cyclopropene are comparably less explored.In this work we studied the Cu-catalyzed reactions of cyclopropene in the presence of several types of nucleophiles,such as phosphites,amides,organoboronic esters,and oximes.These novel reactions have contributed to enrich copper catalysis in the context of different reaction types,such as metal carbenoid reaction,carbometalation and Cope-type hydroamination.Chapter 1 briefly summarized the structure and chemistry of cyclopropene.Chapter 2 put forward research proposal Based on the development of cyclopropene.In Chapter 3 we studied the Cu-catalyzed coupling reaction of cyclopropene with phosphites and amides,affording a series of allylic derivatives.The reaction probably proceeds through an allyl copper(I)species via cyclopropene ring-opening,which undergoes protonation to enable stereoselective access to allylphosphonates.The study reveals stereochemistry to be controlled by both ligand and substrate electronics,wherein Hammett analysis support the existence of d-π*interaction in the allylic Cu(I)species.In Chapter 4 we used functionality-tolerant organoboron reagent in lieu of the highly basic Grignard and organozinc reagent,which also enables three-compoent reactivity,enabling a multicomponent access to highly medicinally relevant ACPA derivatives.The novel carbometalation strategy paves the way for the development of other three-component cyclopropene synthesis.In chapter 5 we studied the Cu-catalyzed addition reaction of cyclopropene with oximes for the synthesis of enantioenriched cyclopropyl nitrones.This ligand enabled reaction couples readily available starting materials,operates under mild conditions and displays broad scope and exceptionally high enantio-and diastereocontrol,representing the first high enantioselective nitrone synthesis.Preliminary mechanistic studies support an inner-sphere aminocupration process via a metalla-retro-Cope intermediate.This concept offers completely novel metalπ-activation strategy for the Cope-type hydroamiation of sp~2-hybrodized N-nucleophiles.