Pentaerythritol

Pentaerythritol
IUPAC name 2,2-Bis(hydroxymethyl)1,3-propanediol
Other names Hercules P 6, monopentaerythritol, tetramethylolmethane, THME, PETP, pentaerythrite, Pentek, Hercules Aqualon improved technical PE-200
Identifiers
CAS number	115-77-5 Y
UNII	SU420W1S6N Y
Properties
Molecular formula	C5H12O4
Molar mass	136.15
Appearance	white solid
Density	1.396g/cm3
Melting point	260.5 °C
Boiling point	276 °C at 30 mmHg
Solubility in water	5.6 g/100 mL at 15°C
Hazards
Flash point	200.1°C
Y (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Pentaerythritol is the organic compound with the formula C₅H₁₂O₄. This white, crystalline polyol with the neopentane backbone is a versatile building block for the preparation of many polyfunctionalized compounds such as the explosive PETN and pentaerythritol tetraacrylate.^[1] Derivatives of pentaerythritol are components of alkyd resins, varnishes, PVC stabilizers, tall oil esters, and olefin antioxidants.

Halogen-free pentaerythritol esters are also environmentally friendly alternative to conventional electrical transformer fluids, being both readily biodegradable and non-hazardous in water. They advantageously replace polychlorobiphenyl (PCB), and even silicone-based or fluorinated hydrocarbons, as dielectric fluid in transformers. Their low volatility and high flash point give them an excellent resistance to ignition in case of major electrical failure and transformer rupture.

Synthesis

Pentaerythritol can be prepared by condensation of acetaldehyde and formaldehyde in a basic environment (Tollens' reaction).^[2] The process occurs by successive aldol reactions followed by a Cannizzaro reaction. Impurities include dipentaerythritol and tripentaerythritol.^[3]

2 CH₃CHO + 8 CH₂O + Ca(OH)₂ → 2 C(CH₂OH)₄ + (HCOO)₂Ca

References

1. ^ S. F. Marrian (1948). "The Chemical Reactions of Pentaerythritol and its Derivatives". Chemical Reviews 43 (1): 149–202. doi:10.1021/cr60134a004. PMID 18876970. 
2. ^ H. B. J. Schurink (1941), "Pentaerythritol", Org. Synth., http://www.orgsyn.org/orgsyn/orgsyn/prepContent.asp?prep=CV1P0425 ; Coll. Vol. 1: 425 
3. ^ M. S. Peters, J. A. Quinn (1955). "Pentaerythritol Production Yields". Industrial & Engineering Chemistry 47 (9): 1710–1713. doi:10.1021/ie50549a016.