|Jmol-3D images||Image 1|
|Molar mass||140.186 g/mol|
|Density||1.33 g/cm³ (at 20 °C)|
280 °C (sublimes)
|Solubility in water||85.3 g/100 mL|
|Main hazards||Highly flammable, harmful|
|410 °C (770 °F)|
| (what is: / ?) |
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Hexamethylenetetramine is a heterocyclic organic compound with the formula (CH2)6N4. This white crystalline compound is highly soluble in water and polar organic solvents. It has a cage-like structure similar to adamantane. It is useful in the synthesis of other chemical compounds, e.g. plastics, pharmaceuticals, rubber additives. It sublimes in a vacuum at 280 °C.
Synthesis, structure, reactivity
The molecule has a symmetric tetrahedral cage-like structure, similar to adamantane, whose four "corners" are nitrogen atoms and "edges" are methylene groups. Although the molecular shape defines a cage, no void space is available at the interior for binding other atoms or molecules, unlike crown ethers or larger cryptand structures.
The molecule behaves like an amine base, undergoing protonation and N-alkylation.
The main use of hexamethylenetetramine is in the production of powdery or liquid preparations of phenolic resins and phenolic resin moulding compounds, where it is added as a hardening component. These products are used as binders, e.g. in brake and clutch linings, abrasive products, non-woven textiles, formed parts produced by moulding processes, and fireproof materials.
Outdated Medical Uses
Urotropine in combination with other antibiotics were widespreadedly used back in 1965's to 1990 to deal in combating Urinary Infections until proved for its harmful side effects
- Grocott's methenamine silver stain, used widely as a screen for fungal organisms.
- Jones' stain, a methenamine silver-Periodic acid-Schiff that stains for basement membrane, availing to view the "spiked" GBM associated with membranous glomerulonephritis.
Together with 1,3,5-trioxane, hexamethylenetetramine is a component of hexamine fuel tablets used by campers, hobbyists, the military and relief organizations for heating camping food or military rations. It burns smokelessly, has a high energy density (30.0 MJ/kg), does not liquify while burning, and leaves no ashes.
Standardized 0.149 g tablets of methenamine (hexamine) are used by fire-protection laboratories as a clean and reproducible fire source to test the flammability of carpets and rugs.
Reagent in organic chemistry
Hexamethylenetetramine is a versatile reagent in organic synthesis. It is used in the Duff reaction (formylation of arenes), the Sommelet reaction (converting benzyl halides to aldehydes), and in the Delepine reaction (synthesis of amines from alkyl halides).
Since 1990 the number of European producers has been declining. The French SNPE factory closed in 1990; in 1993, the production of hexamethylenetetramine in Leuna, Germany ceased; in 1996, the Italian facility of Agrolinz closed down; in 2001, the UK producer Borden closed; in 2006, production at Chemko, Slovak Republic, was closed. Remaining producers include INEOS in Germany, Caldic in the Netherlands, and Hexion in Italy. In the US, Eli Lilly and Company stopped producing methenamine tablets in 2002.
- Karsten Eller, Erhard Henkes, Roland Rossbacher, Hartmut Höke "Amines, Aliphatic" in Ullmann's Encyclopedia of Industrial Chemistry, 2005 Wiley-VCH Verlag, Weinheim. doi:10.1002/14356007.a02_001
- Alan H. Schoen (2004), Re: Equialence of methenamine Tablets Standard for Flammability of Carpets and Rugs. U.S. Consumer product Safety Commission, Washington, DC, July 29, 2004.
- A. T. Bottini, Vasu Dev, and Jane Klinck (1963), "Syringic Aldehyde", Org. Synth., http://www.orgsyn.org/orgsyn/orgsyn/prepContent.asp?prep=CV4P0866; Coll. Vol. 4: 866
- Kenneth B. Wiberg (1963), "2-Thiophenaldehyde", Org. Synth., http://www.orgsyn.org/orgsyn/orgsyn/prepContent.asp?prep=CV3P0811; Coll. Vol. 3: 811
- A. T. Bottini, Vasu Dev, and Jane Klinck (1963), "2-Bromoallylamine", Org. Synth., http://www.orgsyn.org/orgsyn/orgsyn/prepContent.asp?prep=CV5P0121; Coll. Vol. 5: 121