382
2
General Synthetic Methods
⊡ Figure 7
Main thermal degradation products from D-glucose
Ab initio molecular dynamics (MD) simulations were also applied in elucidation of xylose and
glucose degradation pathways ( > Scheme 2). In the case of D-xylose 39, a 2,5-anhydride intermediate was observed leading to the formation of furfural 34 through elimination of water. This
pathway agrees with one of the mechanisms proposed in the literature in that no open chain
intermediates were found. In the case of D-glucose 33, a series of intermediates were observed
before forming the 2,5-anhydride intermediate that eventually leads to HMF 38 ( > Fig. 7).
One of these intermediates was a very short-lived open-chain form. Furthermore, two novel
side-reaction pathways were identified, which lead to degradation products other than 38 [52].
⊡ Scheme 2
2
General Synthetic Methods
⊡ Figure 7
Main thermal degradation products from D-glucose
Ab initio molecular dynamics (MD) simulations were also applied in elucidation of xylose and
glucose degradation pathways ( > Scheme 2). In the case of D-xylose 39, a 2,5-anhydride intermediate was observed leading to the formation of furfural 34 through elimination of water. This
pathway agrees with one of the mechanisms proposed in the literature in that no open chain
intermediates were found. In the case of D-glucose 33, a series of intermediates were observed
before forming the 2,5-anhydride intermediate that eventually leads to HMF 38 ( > Fig. 7).
One of these intermediates was a very short-lived open-chain form. Furthermore, two novel
side-reaction pathways were identified, which lead to degradation products other than 38 [52].
⊡ Scheme 2