Oxygen → D-Arabinonic acid, potassium salt (1:1)

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

One suitable example of a reaction for the oxidative decarboxylation of a glucose starting material to arabinonate is provided in U.S. Pat. No. 4,125,559 to Scholz et al., filed May 19, 1977 and issued Nov. 14, 1978, which is provided as Theoretical Example 1. A solution of 396.07 grams of KOH in 10,000 grams of water is introduced into a vertical tubular reactor of 2,000 mm length and 50 mm internal diameter which is packed with V2A steel Raschig rings of 6 mm diameter. The solution is heated to 45° C. and is mixed by means of a centrifugal pump, with a mixing effect corresponding to 1,950 revolutions per minute. 120 grams of oxygen are introduced from the reactor top and the pressure is set to 20.5 bars. In the course of 5 minutes 1,000 grams of an aqueous solution containing 396.32 grams of D-glucose, monohydrate are added, using a metering pump, at the reactor top, to the alkaline solution, which is circulated by means of the centrifugal pump (1,950 revolutions per minute) in a downward direction via the reactor top. The solution is now mixed for 9 hours at 1,950 revolutions per minute and kept at 45° C. and 20.5 bars. It is then concentrated under 15 mbars until 500 grams of residue are left. This material is introduced into 6,000 grams of methanol, while stirring, whereupon crystalline potassium arabinonate precipitates. Filtration gives a theoretical yield of 408.44 grams of potassium arabinonate of melting point 203-204° C. (with decomposition).

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