Effect of metal chlorides on glucose mutarotation and possible implications on humin formation

An in situ Raman spectroscopic kinetic study of the glucose mutarotation reaction is presented herein. The effect of metal chlorides on the ease of the ring opening process is discussed. It is shown that SnCl4 facilitates the mutarotation process towards the -anomer extremely fast, while CrCl3 appears to promote the formation of the -anomer of glucose. The infrared spectra of humins prepared in different Lewis acids underscore the possibility of multiple reaction pathways.