Polymers From Chiral BINOL:Synthesis,properties And Preliminary Application In Asymmetric Catalysis

One of the most basic ways for synthetic helical polymer is the polymerization of chiral monomers.Seeking easy methods for synthesis of chiral monomers is of great significance.BINOL and its derivatives represent a class of important chiral molecules for their modifiable versatile backbones.With appropriate choices of substituents,BINOL derivatives could be transformed into various chiral monomers.In the first part,we synthesized four 3-substituted-3?-vinyl BINOL derivative monomers from(S)-BINOL which include aryl substituent.These monomers were radically polymerized using AIBN as initiators.The preferred-handed helical structures of the obtained polymer were confirmed by comparing the specific optical rotation and CD spectra with their monomers and model compounds.In the second part,we synthesized four 3-substituted-3?-acetenyl BINOL derivative monomers from(S)-BINOL which include aryl substituent.These monomers were monomers were coordination polymerized using [Rh(nbd)2]Cl2/Et3 N as catalyst.The preferred-handed helical structures of the obtained polymer were confirmed by comparing the specific optical rotation and CD spectra with their monomers.In the third part,the synthesis of optically active oxide propane monomers with binaphthyl pendant,the obtained epoxy monomers were anionically polymerized using KOH as initiator,and deprotection of the MOM groups to obtain soluble polyethers.The last part,these polymers were used to induce the enantioselective phenylacetylene additions to aldehydes.The polyethers gave the expected propargyl alcohols with up to 94% yields and 95% ee values.The recovered polyethers could be reused for 6 times to induce the asymmetric addition of phenylacetylene to aldehydes without losing their enantioselective induction ability.In addition,we also have a preliminary study of other model reaction.