General Description
Odorless white crystalline powder. Bitter taste. pH (saturated solution in water): 5.5-7.
Reactivity Profile
THEOBROMINE(83-67-0) may be sensitive to prolonged exposure to light. This chemical has weakly acidic properties, combining with bases to forms salts. THEOBROMINE(83-67-0) also has even weaker basic properties, combining with acids to form salts which are decomposed in aqueous solution. .
Air & Water Reactions
Insoluble in water.
Fire Hazard
Flash point data for this chemical are not available; however, THEOBROMINE is probably combustible.
Description
A purine alkaloid which is present in a number of plants, particularly Theobroma
coco and kola nuts. The alkaloid sublimes at 290°C and may be purified by this
method when it forms colourless, rhombic microcrystals. It is soluble in 1600
parts of H20 at 17°C, insoluble in cold Et20 or ligroin. It is a weak base and the
salts are decomposed by H20. The perchlorate forms colourless crystals of the
monohydrate which decompose at 271-3°C; the mercurinitrate is also crystalline
and has a melting point above 300°C. The mercury salt is obtained as colourless
crystals which darken at 29S-300°C and melt at 310°C. One imino group is
present yielding alkyl derivative, e.g. the N-methyl compound identical with
Caffeine (q.v.); the N~ethyl derivative, m.p. 164-SoC, forming an aurichloride,
m.p. 226°C; N-propyl, m.p. 136°C giving an aurichloride, m.p. 9SoC; N-butyl,
m.p. 119°C and the N-iso butyl, m.p. 129-130oC also giving an aurichloride,m.p. 97°C. The alkaloid also furnishes a methochloride as colourless rods, m.p.
320-340°C (dec.) which is very soluble in H20 and the methoaurichloride, m.p.
265°C (dec.).
Like Caffeine (q.v.) and Theophylline (q.v.), the alkaloid and its salts are
mild stimulants and also possess a diuretic action.
Chemical Properties
A methyl xanthine similar to caffeine. Theobromine has a bitter taste.
Chemical Properties
white to light yellow crystal powder
Occurrence
Reported found in cocoa bean, cocoa powder, cola nut and tea.
Uses
A metabolite of Caffeine
Uses
diuretic, bronchodilator, cardiotonic
Definition
ChEBI: A dimethylxanthine having the two methyl groups located at positions 3 and 7. It is a purine alkaloid derived from cocoa tree.
Hazard
Toxic by ingestion. Questionable carcinogen.
Flammability and Explosibility
Nonflammable
Synthesis
There are two main methods for producing theobromine, one is extracted from cocoa beans or cocoa bean shells. The other is to use monomethylurea and cyanoacetic acid as the starting material, and obtain theobromine products through condensation reactio
Purification Methods
It crystallises from H2O. Its solubility in H2O is 0.06% at 15o and 1.25% at 100o, and it is poorly soluble in organic solvents. It forms salts with heavy metals and is a diuretic, vasodilator and a cardiac stimulant. [Lister Purines Part II, Fused Pyrimidines Brown Ed, Wiley-Interscience pp254-225 1971, ISBN 0-471-38205-1, Beilstein 26 H 457, 26 I 135, 26 II 264, 26 III/IV 2336.]
References
Biltz, Max., Annalen, 423,320 (1921)
Dubosc., Chem. Zentr., IV, 956 (1932)
Gepner, Kreps., Chem. Abstr., 41,96 (1947)
Bohinc, Korber-Smid, J agodic., Farm. Vestn., (Ljubljana), 23, 143 (1972)
