Use of novel substrates for single molecule conductance measurement
Qian Zhang (PhD Student)
In this study, the scanning tunneling microscopy (STM) I(s) method was applied on the conductance measurement of N-alkanedithiol (N = 4, 6, 8, 10, 12) molecules to investigate the length dependence of conductance on the graphene substrate. With the successful formation of gold-N-alkanedithiol-graphene asymmetric junctions, conductance values of N-alkanedithiol molecules were obtained and a decay constant β was calculated as 0.48 per –CH2 group. Our results revealed that graphene substrate shows stable performance to act as an electrode. Thiol group can bind to graphene substrate firmly through the chemical or physical interaction, and as a result, the reliable and reproducible molecular junctions were formed with the conductance of molecules agreed well to previous reported values.
NHCs and NHCs catalyzed carbon-carbon bond formation reactions
Yimei Wu(MRes Student)
NHCs represent a family of the most outstanding catalysts, which have been widely used in carbon-carbon bond-forming reactions. In this talk, a general introduction about carbenes, NHCs and carbon-carbon bond-forming reactions will be given. The synthesis of three types of NHCs and the NHC-catalyzed new reactions as a new approach to the preparation of noscapine will be discussed. Noscapine is a natural product isolated from Papaver somniferum.