A Publication
of Reliable Methods
for the Preparation
of Organic Compounds
Annual Volume
Org. Synth. 1956, 36, 38
DOI: 10.15227/orgsyn.036.0038
[D-Gulonic acid, γ-lactone]
Submitted by J. V. Karabinos1
Checked by R. T. Arnold, Fred Smith, and Bertha Lewis.
1. Procedure
In a 500-ml. glass-stoppered Erlenmeyer flask, 30 g. (0.2 mole) of D-xylose and 10.7 g. (0.2 mole) of ammonium chloride are dissolved in 100 ml. of distilled water. Cracked ice (100 g.) is added to this mixture, followed by 10 g. (0.2 mole) of sodium cyanide, and the solution is maintained at 0–5° for 48 hours. Powdered barium hydroxide octahydrate (63 g., 0.2 mole) is added along with 100 ml. of water to the cyanohydrin mixture (Note 1), which is heated on a steam bath for 2 hours with occasional stirring. The basic barium gulonate (Note 2), which is allowed to separate overnight at 5°, is collected by filtration and washed with cold water (0°) until the washings are chloride-free. Excessive washing of the barium salt is to be avoided because of its solubility. The barium salt is suspended in 200 ml. of water, and the barium ion is precipitated quantitatively by sulfate ion (Note 3). After removal of the barium sulfate by suction filtration, the filtrate and washings are concentrated to a colorless syrup on a steam bath in a stream of dry air (Note 4). The resultant syrup is dissolved in 50 ml. of hot ethylene glycol monomethyl ether (methyl Cellosolve), sufficient ethyl acetate is added to incipient turbidity, and the solution is seeded with D-gulonic-γ-lactone (Note 5). The lactone, which is allowed to crystallize overnight, is collected by suction filtration, washed with ethanol and dried in a vacuum over at 60°. The D-gulonic-γ-lactone (Note 6) has a melting point of 181–183° which is unchanged by recrystallization from aqueous ethanol. The yield is 10.7–11.6 g. (30–33%) (Note 7).
2. Notes
1. The barium hydroxide serves to hydrolyze any unchanged nitriles as well as to precipitate the aldonic acid.
2. The barium gulonate is undoubtedly contaminated with some epimeric idonate. The lactone of the latter substance is removed by recrystallization of the gulonic lactone from methyl Cellosolve.
3. It is convenient to titrate the suspended barium salt with 18N sulfuric acid (approx. 12–14 ml.) to a pH of 1.5 using a pH meter. After removal of the barium sulfate the slight excess of sulfate ion may be precipitated using barium chloride solution. The end point is taken when several drops of filtrate show no turbidity either upon addition of sulfuric acid or barium chloride solution.
4. Concentration in this manner allows sufficient time for the gulonic acid to be converted to the lactone in the presence of a trace of hydrochloric acid. The checkers observed also that an easily crystallized lactone was always obtained if concentration under reduced pressure was employed.
5. Crystallization is speeded considerably by seeding.
6. A small amount of less pure lactone may be obtained by evaporation of the mother liquor to a syrup and repetition of the methyl Cellosolve-ethyl acetate crystallization.
7. The submitter has reported yields up to 39% using the above procedure.
3. Discussion
The present method is adapted from that of Fischer2 employing recently developed modifications of the cyanohydrin synthesis.3,4

References and Notes
  1. Blockson Chemical Company, Joliet, Illinois.
  2. Fischer and Stahel, Ber., 24, 528 (1891).
  3. Karabinos, Hann, and Hudson, J. Am. Chem. Soc., 75, 4320 (1953).
  4. Isbell, Karabinos, Frush, Holt, Schwebel, and Galkowski, J. Research Natl. Bur. Standards, 48, 163 (1952).

Chemical Abstracts Nomenclature (Collective Index Number);
(Registry Number)

ethanol (64-17-5)

sulfuric acid (7664-93-9)

hydrochloric acid (7647-01-0)

ethyl acetate (141-78-6)

ammonium chloride (12125-02-9)

sodium cyanide (143-33-9)

barium chloride (10361-37-2)

barium sulfate (7727-43-7)

barium hydroxide (17194-00-2)

barium hydroxide octahydrate (12230-71-6)

methyl Cellosolve,
ethylene glycol monomethyl ether (109-86-4)

d-Gulonic acid, γ-lactone (6322-07-2)


barium gulonate

gulonic lactone

gulonic acid