Conformational change in a urea catalyst induced by sodium cation and its effect on enantioselectivity of a Friedel-Crafts reaction
作者:Arjun K. Chittoory、Gayatri Kumari、Sudip Mohapatra、Partha P. Kundu、Tapas K. Maji、Chandrabhas Narayana、Sridhar Rajaram
DOI:10.1016/j.tet.2014.03.068
日期:2014.5
indeed in an unfavorable conformation. Infrared and Raman spectroscopic studies show that sodium binds the catalyst through the carbonyl and sulfonyl groups. Simulated IR and Raman spectra match well with the experimentally recorded spectra, thereby corroborating the proposed conformational change. This result shows that weak Lewis acids can be used to tune the conformation of hydrogen-bonding catalysts