Study of stereochemical effect of galactoside mixture based on reaction time

The research project that had been conducted is the study of stereochemical effect of galactoside mixtures based on reaction time, referring to three different time period which are 12 hour, 24 hour and 48 hours. The reaction occur in this research is between galactose and palm kernel oil alcohol. With the present of lithium aluminium hydride, LiAlH4 as catalyst, the configuration of galactoside will be formed, whether it is in αgalactoside form or β-galactoside form. The amount of production of each configuration depends on the period of time of reaction. NMR Spectroscopy is used to determine the ratio of these galactoside’s configuration. In 12 hour time reaction, both α and β galactoside configuration are in an equal ratio which are 1:1. The second reaction time which is 24 hour yield a ratio of α and β galactosides configuration from ~2:1. And the final reaction time which is 48 hours had produced a ratio of ~8:1. This ratio is too high for this time reaction, which α-galactoside configuration produced is too high. There may be some error in analyzing the compound of some error during conducting the experiment. Theoretically, the ratio can be taken because the formation of α-galactoside is increase with increase of reaction time and formation of βgalactoside decrease with increase of reaction time. The research project also involve investigating the ratio produced by two stereoisomers of palm kernel oil derived galactosides, which are the alpha-galactosides and the beta-galactoside. The research conduct by synthesizing galactoside through three different step, which are peracytelation of galactose, glycosylation of galactoside and deacytelation of galactosdie. Three reaction time are 12 hour, 24 hour and 48 hour were done to study the α-galactoside and β galactosides ratio changes. The ratio of production of both αgalactoside and β-galactoside were measured from the NMR results. Based from NMR results obtained, the ratio of more favourable to α-galactoside as time period is longer. This proven that α-galactoside takes more time to form because it is harder to stable in early codition while β-galactoside produce more in earlier stage as it is more stable, making it easier to form.