2H-Pyran, 3,4-dihydro-

• Formula: C₅H₈O
• Molecular weight: 84.1164
• IUPAC Standard InChI: InChI=1S/C5H8O/c1-2-4-6-5-3-1/h2,4H,1,3,5H2 Copy

  
• IUPAC Standard InChIKey: BUDQDWGNQVEFAC-UHFFFAOYSA-N Copy
• CAS Registry Number: 110-87-2
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
  The 3d structure may be viewed using Java or Javascript.
• Species with the same structure:
  • Pyran, 2,3-dihydro-
  • Dihydropyran
• Other names: Dihydropyran; 2,3-Dihydro-4H-pyran; 2H-3,4-Dihydropyran; 3,4-Dihydro-2H-pyran; 3,4-Dihydropyran; 5,6-Dihydro-4H-pyran; 2,3-Dihydropyran; 3,4-Dihdro-2H-pyrane; 3,4-Dihydro-2-pyran; δ2-Dihydropyran; Pyran, dihydro-; 1,2-Pyran, 3,4-dihydro-; NSC 57860
• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Phase change data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • Gas Chromatography
• Data at other public NIST sites:
  • Computational Chemistry Comparison and Benchmark Database
  • Gas Phase Kinetics Database
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Gas phase thermochemistry data

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow

Constant pressure heat capacity of gas

Condensed phase thermochemistry data

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Reaction thermochemistry data

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.

Individual Reactions

 +  =

By formula: C₅H₈O + H₂ = C₅H₁₀O

Gas phase ion energetics data

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias
L - Sharon G. Lias

Data compiled as indicated in comments:
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

Ionization energy determinations

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Steele, Chirico, et al., 1989
Steele, W.V.; Chirico, R.D.; Nguyen, A.; Hossenlopp, I.A.; Smith, N.K., Determination of some pure compound ideal-gas enthalpies of formation, AIChE Symp. Ser., 1989, 85, 140-162. [all data]

Dorofeeva O.V., 1992
Dorofeeva O.V., Ideal gas thermodynamic properties of oxygen heterocyclic compounds. Part 2. Six-membered, seven-membered and eight-membered rings, Thermochim. Acta, 1992, 200, 121-150. [all data]

Allinger, Glaser, et al., 1981
Allinger, N.L.; Glaser, J.A.; Davis, H.E., Heats of hydrogenation of some vinyl ethers and related compounds, J. Org. Chem., 1981, 46, 658-661. [all data]

Hunter and Lias, 1998
Hunter, E.P.; Lias, S.G., Evaluated Gas Phase Basicities and Proton Affinities of Molecules: An Update, J. Phys. Chem. Ref. Data, 1998, 27, 3, 413-656, https://doi.org/10.1063/1.556018 . [all data]

Bloch, Brogli, et al., 1978
Bloch, M.; Brogli, F.; Heilbronner, E.; Jones, T.B.; Prinzbach, H.; Schweikert, O., 138. Photoelectron spectra of unsaturated oxides. I. 1,4- dioxin and related systems, Helv. Chim. Acta, 1978, 61, 1388. [all data]

Planckaert, Doucet, et al., 1974
Planckaert, A.A.; Doucet, J.; Sandorfy, C., Comparative study of the vacuum ultraviolet absorption and photoelectron spectra of some simple ethers and thioethers, J. Chem. Phys., 1974, 60, 4846. [all data]

Watanabe, Nakayama, et al., 1962
Watanabe, K.; Nakayama, T.; Mottl, J., Ionization potentials of some molecules, J. Quant. Spectry. Radiative Transfer, 1962, 2, 369. [all data]

Batich, Heilbronner, et al., 1976
Batich, C.; Heilbronner, E.; Quinn, C.B.; Wiseman, J.R., The electronic structure of vinyl ethers and sulfides with interrupted conjugation examined by photoelectron spectroscopy, Helv. Chim. Acta, 1976, 59, 512. [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, References

• Symbols used in this document:
  

  Cp,gas	Constant pressure heat capacity of gas
  IE (evaluated)	Recommended ionization energy
  ΔcH°liquid	Enthalpy of combustion of liquid at standard conditions
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfH°liquid	Enthalpy of formation of liquid at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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