| Carbon-hydrogen bonds(C-H)are widely found in organic compounds.Due to the high bond energy and low polarity of C-H bonds,they are inert in conventional chemical reactions.At the same time,the presence of multiple similar C-H bonds in organic compounds makes selective activation of C-H bonds at specific positions even more challenging.In recent years,chemists have developed a series of transition metal-catalyzed C-H bond activation functionalization reactions with the help of the guide group strategy.Among them,8-aminoquinoline guide group and pyridinecarbonyl guide group are most widely used in C-H bond functionalization reactions.In this thesis,Cu-catalyzed C-H bond amination reactions of ferrocene derivatives and Pd-catalyzed asymmetric C-H bond allylation reactions of oligopeptide derivatives have been investigated with the help of the guide group strategy,the main contents are as follows:1.Cu-catalyzed C-H bonded amination of ferrocene derivativesThe Cu-catalyzed monoamination of ferrocenamides adjacent to C-H bonds was achieved using 8-aminoquinoline as the guide group.The reaction conditions were mild and a series of secondary amines including bioactive molecules were suitable for the reaction and gave amination products in moderate to good yields,reflecting the good functional group compatibility of the reaction.The gram-level reaction yields were good and the guide groups could be easily removed under basic conditions.2.Pd-catalyzed asymmetric C-H bonded allylation of oligopeptide derivativesPd-catalyzed asymmetric C-H bonded allylation reactions of peptides were achieved using pyridinecarbonyl as a directing group.The reaction used inexpensive pyroglutamic acid as a chiral ligand and α-methacrylate as the actual allylation to synthesize a series of enantiomeric N-aryl peptide blocking isomers with 1,1-di-substituted olefins in excellent yields and enantioselectivities(up to 90% yield,up to 97% ee). |
