TY - JOUR
T1 - Enantioselective C - C Bond Formation Enhanced by Self-Assembly of Achiral Surfactants
AU - Iwasaki, Fumihiko
AU - Suga, Keishi
AU - Okamoto, Yukihiro
AU - Umakoshi, Hiroshi
N1 - Funding Information:
This work was supported by the Funding Program for Next Generation World-Leading Researchers of the Council for Science and Technology Policy (CSTP) (GR066), JSPS Grant-in-Aid for Scientific Research A (26249116), and JSPS Grant-in-Aid for Research Activity Start-up (25889039). One of the authors (F.I.) also expresses his gratitude to the Japan Society for the Promotion of Science (JSPS) scholarships, Research Fellow of Japan Society for the Promotion of Science (16J05458). The authors also thank Daicel Corp., CPI Company, for their kind advice on optimizing the conditions for HPLC analysis using a chiral column.
Publisher Copyright:
© 2017 American Chemical Society.
PY - 2017/4/30
Y1 - 2017/4/30
N2 - The use of achiral surfactant assemblies as a reaction platform for an alkylation reaction resulted in a high enantiomeric excess. Dilauryldimethylammonium bromide (DDAB) vesicles were modified with cholesterol to promote alkylation of N-(diphenylmethylene)glycine tert-butyl ester (DMGBE) with benzyl bromide, resulting in high conversion (∼90%) and high enantioselectivity (up to 80%). The R-enantiomer was formed on using the DDAB vesicles, whereas the use of phospholipid liposomes prepared from 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) produced an excess of the S-enantiomer. Considering the chemical structures of the reaction substrates and amphiphiles as well as the membrane structures and properties of DDAB vesicles and DOPC liposomes, it is suggested that the enantiomeric excesses result from the location of the quaternary amine of the amphiphiles and the DMGBE at the outer surface of the membrane. We show that the enantioselective reaction at the surface of the self-assembly could be regulated by adjusting the chemical structures and resulting membrane properties of the self-assembly.
AB - The use of achiral surfactant assemblies as a reaction platform for an alkylation reaction resulted in a high enantiomeric excess. Dilauryldimethylammonium bromide (DDAB) vesicles were modified with cholesterol to promote alkylation of N-(diphenylmethylene)glycine tert-butyl ester (DMGBE) with benzyl bromide, resulting in high conversion (∼90%) and high enantioselectivity (up to 80%). The R-enantiomer was formed on using the DDAB vesicles, whereas the use of phospholipid liposomes prepared from 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) produced an excess of the S-enantiomer. Considering the chemical structures of the reaction substrates and amphiphiles as well as the membrane structures and properties of DDAB vesicles and DOPC liposomes, it is suggested that the enantiomeric excesses result from the location of the quaternary amine of the amphiphiles and the DMGBE at the outer surface of the membrane. We show that the enantioselective reaction at the surface of the self-assembly could be regulated by adjusting the chemical structures and resulting membrane properties of the self-assembly.
UR - http://www.scopus.com/inward/record.url?scp=85028933145&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85028933145&partnerID=8YFLogxK
U2 - 10.1021/acsomega.7b00034
DO - 10.1021/acsomega.7b00034
M3 - Article
AN - SCOPUS:85028933145
SN - 2470-1343
VL - 2
SP - 1447
EP - 1453
JO - ACS Omega
JF - ACS Omega
IS - 4
ER -