Annulation Of Earth Abundant Metals Stabilized Amphoteric Intermediates And Amphoteric Molecules

Annulation reaction of transition metal stabilized amphoteric intermediates and amphoteric molecules is an efficient and powerful method for the construction of cyclic compounds,which has been widely used in organic synthesis.In this dissertation,recent advances in this field were reviewed in detail and related annulations of earth abundant metals stabilized amphoteric intermediates and amphoteric molecules were investigated.The detailed works were described as below:First,we chose the readily available vinyl benzoxazinanones and sulfur ylides as starting materials.In the presence of nucleophilic iron catalyst,the vinyl benzoxazinanones will generate allyl iron complex stabilized amphoteric intermediates through releasing a molecule of CO2,and this intermediates were trapped by sulfur ylides to undergo formal[4+1]cycloadditions.A wide range of highly functionalized indoline products were isolated in good yields and with high stereoselectivities.Meanwhile,further transformation of indoline product gave tetrahydrocarbazole containing a dihydroindene unit.In addition,a possible reaction mechanism was proposed based on a series of control experiments,which were complemented by DFT calculations.Based on the iron-catalyzed decarboxylative formal[4+1]cycloadditions,we designed a new reagent:ethynyl benzoxazinanones.In the presence of chiral copper catalyst,the ethynyl benzoxazinanones will generate copper-allenylidene stabilized amphoteric intermediates through releasing a molecule of CO2,and these intermediates were trapped by in situ generated sulfur ylides to undergo formal[4+1]cycloadditions.A wide range of highly functionalized chiral indoline products and related cycloadducts were obtained with high yields,enantioselectivities and stereoselectivities(up to 99%yield,98%ee and>95:5 dr).Further synthetic transformation of products produced 1,2,3-triazolesubstituted chiral indoline and 2-indole-substituted chiral indoline.In addition,based on the nonlinear relationship between the enantiopurity of product and chiral copper catalyst and also precedent report,a possible reaction mechanism was proposed.Furthermore,a possible symmetric induction mode was also proposed based on the absolute configuration of an indoline product through X-ray crystallographic analysis.Moveover,we also studied the reactivity of readily accessible phenol blocked O/N-substituted isocyanates.These precersors would generate O/N-substituted isocyanates in the presence of base and then go though substitution/cyclization sequence reaction with 2-iodoanilines and 2-iodobenzylamines with the help of copper catalyst in cascade or one pot reaction manner.This method allowed rapid synthesis of 1-alkoxybenzimidazolones,1-alkoxy(amino)-3,4-dihydroquin-azolin-2(1H)-ones and hydrazinylbenzo[d]thiazoles.Meanwhile,synthetic transformation of products gave free hydroxyamic acid heterocycles.Finally,we designed and synthesized a new nitrogen heterocyclic carbene catalyst precursor from chiral proline and it has been successfully applied to annulation reaction of vinyl benzoxazinanones and aryl aldehydes.Thus,varieties of novel indoline-containing moleculeswere efficiently synthesized.In addition,the structure of an indoline product was confirmed by X-ray crystallographic analysis and a possible mechanism was proposed.