The Mechanism Study Of Rhodium-catalysed Functionalization Of Alkenes Initiated By C-H Activation

Organic syntheses that involve the functionalization of non-activated C-H bonds are an attractive research field,which maximize atom-and step-economy,and simplify chemical synthesis.Because the C-H bonds of alkene are chemically stable,the functionalization of alkenes usually requires harsh reaction conditions and drastically limits their use in the syntheses of complex organic molecules.By studying the mechanistic aspects of C-H activation over recent years,great achievements have been made in the design and development of new reaction protocols that proceed efficiently under mild conditions and benefit from improved functional group tolerance and selectivity.In the first part of this thesis,I will report the mechanism of methanol-assisted phthalimide ring opening process.Both the concerted and stepwise mechanisms of the process have been studied.The influence of solvent effects to the ring opening process are further studied.The applicability of the stepwise ring-opening mechanism has been predicted.In the second part,I will introduce the Rhodium-catalysed syn-carboamination of alkenes in methanol solvent.The N-enoxyphthalimides are the source of both the carbon and nitrogen functionalities to stereoselectively incorporate with alkenes.I will report that the Rh(III)-Rh(V)-Rh(III)catalytic process is more kinetically favorable.I will also discuss the competition between the main reaction and side reaction by analyzing the energy barriers of related transition states.