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The direct conversion of cellulose with metal-triflate catalysts in methanol is investigated. Sn II -triflate remarkably catalyzes the formation of a mixture of useful α-hydroxy esters such as methyl lactate, methyl vinyl glycolate and methyl-4-methoxy-2-hydroxybutanoate, on top of methyl levulinate. Compared to other metal triflates or Sn salts, the catalytic features of Sn II -triflate are distinct and linked to the interplay between its Brønsted and Lewis acidic component. A total ester yield (carbon-based, mol%) in the 60%-range could be obtained from cellulose after 2 h at 200 °C for cellulose loadings up to 20 g L −1 with 4.8 mM of catalyst. The cascade reaction network, confirmed by feeding intermediates, highlights the importance of a fast retro-aldol of the hexose intermediates – opposed to their dehydration – when α-hydroxy esters are targeted. By manipulating the triflate-to-Sn ratio, nearly 40% of α-hydroxy esters can be produced in a one-pot approach. Such mixtures could help fuel the demand for functional biodegradable polyesters. [ABSTRACT FROM AUTHOR]