Epimerization of sugars, in particular of D-arabinose to D-ribose

US4778531A · kind A · utility

Assignee

• BASF SE

Inventors

• Walter Dobler · Schwetzingen, DE
• Hansgeorg Ernst · Speyer, DE
• Joachim Paust · Schifferstadt, DE

Key dates

• Filing date: Jun 30, 1987
• Grant date: Oct 18, 1988
• Expiry date: Jun 30, 2007

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07H3/02
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Pentoses and hexoses are epimerized by heating sugar dissolved in a solvent in the presence of a molybdenum(VI) compound, by an improved process in which, for the preparation of a sugar having cis OH groups in the 2- or 3-position, of the formula Ia or Ib ##STR1## where R is one of the radicals ##STR2## a homogeneous solution of the corresponding sugar of the formula IIa or IIb ##STR3## is heated to 75.degree.-100.degree. C. in the presence of from 30 to 200 mol %, based on sugar used, of a metal salt of the formula (III) EQU MeX.sub.2 (III) where Me is Mg, Ca, Sr, Ba or Zn and X is Cl or Br, which may or may not contain water of crystallization, and in the presence of from 2 to 20 mol %, based on the sugar used, of a molybdenum(VI) compound. The process is particularly important for the preparation of D-ribose, which is required as an intermediate for vitamin B.sub.2.