Hamashima Synthetic Organic Chemistry Laboratory

We address the following challenges.

１. Development of Novel Catalytic Reactions and Asymmetric Synthesis

We have been engaged in asymmetric catalysis using transition metal complexes, and also developed various efficient methods for incorporating fluorine atoms that are useful for designing new functional molecules. A significant advance of these reactions is expected to allow for more environmentally-benign pharmaceutical synthesis.

Nickel catalysis recently developed in our group, with an effective combination of subsequent catalysis toward one-pot multicomponent reaction, can be extremely useful as a streamlined synthetic method for multisubstituted heterocycles which are integral component of medicinal remedy.

As concerns fluorine chemistry, we take on a challenge to develop novel synthetic methods for fluorine-containing chiral  building blocks commonly needed multistep syntheses.  We apply them to the efficient synthesis of therapeutics and its lead compounds with a combination of recent achievements in our trifluoromethylation (CF₃) and asymmetric bromocyclization.

２. Transformation of Unactivated C(sp³)–H Bonds

At present, direct utilization of ubiquitous C(sp₃)-H bonds of alkane into addition reaction is outside the bounds of possibility in terms of the rules in organic chemistry.  Therefore, innovative and creative idea is required to actualize this formidable challenge. On the other hand, as you look at the reaction of a living body, electron and hydrogen radical transfer processes are managed in stable C-H bond cleavage, harnessing the energy of sunlight.  We design and synthesize new catalysts with such essence and advantages of bioinorganic chemistry, accomplishing the direct transformation of C(sp₃)-H bonds of alkane.

３. Peptide Hydrolysis Catalyst and Control Regulation of Biological Functions

Cleavage of chemically stable peptide bonds under physiological conditions is standing in the center of attention of chemists.  Since conventional amide hydrolysis under harsh reaction conditions is a difficult operation to carry out in the presence of other functionalities, a mild procedure for the hydrolysis is distinctly of great interest. 

We believe transition metal hydroxo complexes developed in our group, allowing them to function as hydrolysis catalysts, have a good potential to enable such an efficient methodology. As part of our research on the development of green chemistry, we design and discover hydroxo complex catalysts stable in water, applying them into biologically-relevant catalysis.