The Design And Synthesis Of Novel Optically Active Cagelike Molecule

Optically active cyclophanes, such as helical molecules and three-dimensional, cagelike cyclophanes have been the subject of extensive investigation from the standpoints of structural chemistry and material science. The fundamental sources of the interest in cyclophanes include the conception of novel, aesthetically pleasing and interesting structures, the challenge of synthesizing them, and the study of their properties once they had been prepared. Their unique structural features (π-conjugated, helicity) indicate their potential applications in optics and electronics. In this thesis, based on the preceding research of our laboratory, a new type of cagelike cyclophanes, in which 1,1'-binaphthyl unit ,the source of chirality connected by ethynyl was designed and synthesized successfully and their optical properties were preliminarily researched.In the second chapter, a rational synthetic route for enantiopure 2,2'- diethynyl-1,1'-binaphthyl was established. From the optically active 2, 2'-dihydroxy-1,1'-binaphthyl, through esterification, Kumada coupling, bromization, hydrolization and Wittig elimination reaction, 2,2'-diethynyl-1,1'-binaphthyl was obtained.In the third chapter, the design and synthesis of enantiopure compounds with cage structure were described. Enantiopure molecule square--(R,R,R,R,R,R)- and (S,S,S,S,S,S)-23 were synthesized from (R)- and (S)-2,2'-diethynyl-1,1'-binaphthyl templates by several steps including the introduction of protecting group, intermolecular coupling reaction, removal of protecting group, and intermolecular cross-coupling cyclization. In addition, via the linking of m-phenylene, compounds (R,R,R,R,R,R)- and(R,R,R,R,R,R)-, with cage structure were designed and synthesized from (R)- and (S)-2,2'-diethynyl-1,1'-binaphthyl templates. These compounds have the same building block and involve six units of binaphthyl. In the synthesis of compounds (R,R,R,R,R,R)-23 and (S,S,S,S,S,S)-23, the decomposition of TMS group in common Eglinton reaction was successfully avoided by the homocoupling of alkyne under Sonogashira reaction condition.The circular dichroism (CD) spectra, specific rotations ([α]D25) and UV spectra of these compounds were characterized. Their CD spectras represented exactly mirror images of each other, which reflected unambiguously enantiomeric relation between two isomers. The space models of these compounds were obtained and the cavity sizes of these compounds were calculated using Chem3D. The cavity size of the target compound is 1.8 nm, which are 1-3 times of the diameter of C60. Study on the cavity sizes of these compounds is of great significance to host-guest chemistry.So, in this thesis, a new type of cagelike cyclophanes with novel, aesthetically pleasing and interesting structures, in which three different linkers were connected to the 2- and 2'-positions of a 1, 1'-binaphthalene template with ethynyl was designed and synthesized successfully.