Triethyl orthoformate

Triethyl orthoformate
Structural formula
Ball-and-stick model
Names
Preferred IUPAC name
(Diethoxymethoxy)ethane
Other names
Triethoxymethane; Ethyl orthoformate
Identifiers
3D model (JSmol)
ChEMBL
ChemSpider
ECHA InfoCard 100.004.138 Edit this at Wikidata
EC Number
  • 204-550-4
UNII
UN number 2524
  • InChI=1S/C7H16O3/c1-4-8-7(9-5-2)10-6-3/h7H,4-6H2,1-3H3 ☒N
    Key: GKASDNZWUGIAMG-UHFFFAOYSA-N ☒N
  • InChI=1/C7H16O3/c1-4-8-7(9-5-2)10-6-3/h7H,4-6H2,1-3H3
    Key: GKASDNZWUGIAMG-UHFFFAOYAW
  • CCOC(OCC)OCC
Properties
C7H16O3
Molar mass 148.202 g·mol−1
Density 0.891 g/mL
Melting point −76 °C (−105 °F; 197 K)
Boiling point 146 °C (295 °F; 419 K)
Hazards
GHS labelling:
GHS02: FlammableGHS07: Exclamation mark
Warning
H226, H315, H319, H335
P210, P233, P240, P241, P242, P243, P261, P264, P271, P280, P302+P352, P303+P361+P353, P304+P340, P305+P351+P338, P312, P321, P332+P313, P337+P313, P362, P370+P378, P403+P233, P403+P235, P405, P501
Safety data sheet (SDS) Fischer Scientific
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is checkY☒N ?)

Triethyl orthoformate is an organic compound with the formula HC(OC2H5)3. This colorless volatile liquid, the ortho ester of formic acid, is commercially available. The industrial synthesis is from hydrogen cyanide and ethanol.[1]

It may also be prepared from the reaction of sodium ethoxide, formed in-situ from sodium and absolute ethanol, and chloroform:[2]

CHCl3 + 3 Na + 3 EtOH → HC(OEt)3 + 3⁄2 H2 + 3 NaCl

Triethyl orthoformate is used in the Bodroux-Chichibabin aldehyde synthesis, for example:[3]

RMgBr + HC(OC2H5)3 → RC(H)(OC2H5)2 + MgBr(OC2H5)
RC(H)(OC2H5)2 + H2O → RCHO + 2 C2H5OH

In coordination chemistry, it is used to convert metal aquo complexes to the corresponding ethanol complexes:[4]

[Ni(H2O)6](BF4)2 + 6 HC(OC2H5)3 → [Ni(C2H5OH)6](BF4)2 + 6 HC(O)(OC2H5) + 6 HOC2H5

Triethyl orthoformate (TEOF) is an excellent reagent for converting compatible carboxylic acids to ethyl esters. Such carboxylic acids, refluxed neat in excess TEOF until low-boilers cease evolution, are quantitatively converted to the ethyl esters, without need for extraneous catalysis.[5] Alternatively, added to ordinary esterifications using catalytic acid and ethanol, TEOF helps drive esterification to completion by converting the byproduct water formed to ethanol and ethyl formate.

See also

References

  1. ^ Ashford's Dictionary of Industrial Chemicals, Third edition, 2011, page 9288
  2. ^ W. E. Kaufmann and E. E. Dreger (1941). "Ethyl orthoformate". Organic Syntheses; Collected Volumes, vol. 1, p. 258.
  3. ^ G. Bryant Bachman (1943). "n-Hexaldehyde". Organic Syntheses; Collected Volumes, vol. 2, p. 323.
  4. ^ Willem L. Driessen, Jan Reedijk "Solid Solvates: The Use of Weak Ligands in Coordination Chemistry" Inorg. Synth., 1992, Vol. 29,111–118. doi:10.1002/9780470132609.ch27
  5. ^ Paine, John B. (July 2008). "Esters of Pyromellitic Acid. Part I. Esters of Achiral Alcohols: Regioselective Synthesis of Partial and Mixed Pyromellitate Esters, Mechanism of Transesterification in the Quantitative Esterification of the Pyromellitate System Using Orthoformate Esters, and a Facile Synthesis of the Ortho Pyromellitate Diester Substitution Pattern". The Journal of Organic Chemistry. 73 (13): 4929–4938. doi:10.1021/jo800543w. ISSN 0022-3263. PMID 18522420.