Ga. Attard et al., Temperature effects in the enantiomeric electro-oxidation of D- and L-glucose on Pt{643}(S), J PHYS CH B, 103(9), 1999, pp. 1381-1385
The temperature dependence of the enantioselective adsorption of D- and L-g
lucose on a chiral Pt{643}(S) electrode is reported. The contribution to th
e electro-oxidation current of the initial adsorption of the glucose molecu
le on {111} terrace sites is used to determine a difference in the activati
on energy of adsorption between D- and L-glucose on Pt{643}(S). A value of
approximately 1.4 kJ mol(-1) is obtained, When this value is converted into
a diastereomeric product ratio, the mole percentage of the major product i
s evaluated as being 64%. Although small, it is speculated that optimizatio
n of the average terrace width of the chiral electrode surface will lead to
an increase in the stereoselectivity of the reaction. These measurements c
onstitute the first quantitative determination of enantiomeric selectivity
at a metal electrode in the absence of a chiral promoter.