Download Synthesis of molecule with high optical rotation for the design of

Synthesis of molecule with high optical rotation for the design of chirowaveguides
Laboratoire de Chimie de ENS de Lyon
Laure Guy (Ig R) [email protected] , 04 72 72 83 95
Organic materials have been of increased interest for a number of years because of their applications in
electronic and in our day to day live such as high resolution rich color flat panel TVs or solar panels. The advantage of
organic materials is due to their high functionality, fabrication flexibility, substrate compatibility, affordability, etc. In the
area of the opto-electronic, there has been an explosive growth and development of both organic materials and organic
devices. Representative examples include waveguide based integrated-optic devices, electroluminescent devices,
photovoltaic cells and sensors. The objective of our research is to add a new functionality to organic optical devices: the
chirality. This novel property can lead to the design of a new class of optical devices described in the literature: the
chirowaveguide. We target the field of chiral sensing where chirowaveguides promise to be effective and because it
corresponds to an increasing demand in the environmental and life sciences. However, the main issue to overcome on
the route to chirowaveguides is the access to high optical rotation materials.
Thus, there is a need to design new transparent molecules with high specific OR. It
seems that the best candidates can be found in the helicenes family. Unfortunately these
molecules are very difficult to synthesize, at a scale large enough and as pure enantiomers, to
produce optical waveguides. We have recently proposed the synthesis of a new family of
helicene like compounds (Erreur ! Source du renvoi introuvable.) that respects the
requirements needed for the wave guiding properties. Those requirements are the following: (i)
Figure 1 Example of helicene-­‐like high OR in transparency region, (ii) large scale availabilities as pure enantiomers, (iii)
molecules in our group isotropy.
During our investigations we have pointed out the uncommon behavior of compound 1 (Figure 2). Indeed, this
bis-tetralone is a conglomerat, it means that it crystallizes in a homochiral fashion and some very efficient resolution has
been achieved (preferential crystallization).
Figure 2 : Bis-tetralone as a key intermediates for new chiral compounds with axial chirality
The objective of this project is to take advantage of the easy resolution of compound 1 to develop the synthesis
of new derivatives with axial chirality as pure enantiomers. This work involves mainly organic synthesis and
characterization related to chirality: Chiral HPLC, polarimetry, and circular dichroism.