Zinc oxide as a formose catalyst

Zinc oxide heterogeneously catalyzes formaldehyde condensation to a complex mixture of formose sugars. The reaction proceeds at pH 5.5 and unwanted Cannizzaro side reaction does not occur. The catalyzed reaction is exceptionally slow. At 100°C and 1.00 M ZnO, 0.61 M HCHO starting concentration, the induction period lasts 70 h and 90% conversion does not occur until 92 h. Either addition of D-glucose co-catalyst or reduction in the starting ratio of HCHO to ZnO eliminates the induction period.

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. pH=5,5 . . 100°C ZnO 1,00 M HCHO 0,61 M 70 , 90%- 92 . -D-, HCHO ZnO