Tetrahydropyran
- Formula: C5H10O
- Molecular weight: 86.1323
- IUPAC Standard InChIKey: DHXVGJBLRPWPCS-UHFFFAOYSA-N
- CAS Registry Number: 142-68-7
- 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. - Other names: Oxacyclohexane; Oxane; 2H-Pyran, tetrahydro-; Pentamethylene oxide; Tetrahydro-2H-pyran; THP
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Gas phase thermochemistry data
Go To: Top, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, References, Notes
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
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°gas | -53.50 ± 0.24 | kcal/mol | Cm | Pell and Pilcher, 1965 | ALS |
ΔfH°gas | -52.6 ± 0.6 | kcal/mol | Ccb | Snelson and Skinner, 1961 | ALS |
ΔfH°gas | -53.39 ± 0.37 | kcal/mol | Ccb | Cass, Fletcher, et al., 1958 | Reanalyzed by Cox and Pilcher, 1970, Original value = -50.7 kcal/mol; ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔcH°gas | -758.44 ± 0.23 | kcal/mol | Cm | Pell and Pilcher, 1965 | Corresponding ΔfHºgas = -53.39 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS |
Constant pressure heat capacity of gas
Cp,gas (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
8.102 | 50. | Dorofeeva O.V., 1992 | p=1 bar. Selected values are in close agreement with those calculated by [ Vedal D., 1975].; GT |
9.947 | 100. | ||
12.68 | 150. | ||
15.84 | 200. | ||
21.52 | 273.15 | ||
23.70 ± 0.72 | 298.15 | ||
23.86 | 300. | ||
32.765 | 400. | ||
40.872 | 500. | ||
47.729 | 600. | ||
53.456 | 700. | ||
58.270 | 800. | ||
62.340 | 900. | ||
65.803 | 1000. | ||
68.757 | 1100. | ||
71.286 | 1200. | ||
73.456 | 1300. | ||
75.325 | 1400. | ||
76.941 | 1500. |
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 as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°liquid | -60.9 ± 0.4 | kcal/mol | Ccb | Snelson and Skinner, 1961 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔcH°liquid | -750.94 ± 0.31 | kcal/mol | Ccb | Snelson and Skinner, 1961 | Corresponding ΔfHºliquid = -60.89 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS |
ΔcH°liquid | -752.8 ± 1.5 | kcal/mol | Ccb | Cass, Fletcher, et al., 1958 | Corresponding ΔfHºliquid = -59.0 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS |
ΔcH°liquid | -749.90 ± 0.20 | kcal/mol | Ccb | Skuratov, Strepikheev, et al., 1957 | Reanalyzed by Cox and Pilcher, 1970, Original value = -750.1 ± 0.2 kcal/mol; Combustion at 293 K; Corresponding ΔfHºliquid = -61.93 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS |
Constant pressure heat capacity of liquid
Cp,liquid (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
35.755 | 298.15 | Inglese, Grolier, et al., 1984 | DH |
35.662 | 298.15 | Inglese, Castagnolo, et al., 1981 | DH |
33.60 | 298. | Conti, Gianni, et al., 1976 | DH |
36.121 | 297.62 | Moelwyn-Hughes and Thorpe, 1964 | T = 297 to 327 K.; DH |
Phase change 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:
BS - Robert L. Brown and Stephen E. Stein
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
AC - William E. Acree, Jr., James S. Chickos
DRB - Donald R. Burgess, Jr.
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tboil | 361.0 ± 0.7 | K | AVG | N/A | Average of 8 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Tfus | 224. | K | N/A | Guieu, Carbonnel, et al., 1985 | Crystal phase 1 phase; Uncertainty assigned by TRC = 0.1 K; TRC |
Tfus | 224.15 | K | N/A | Brooks and Pilcher, 1959 | Uncertainty assigned by TRC = 1. K; TRC |
Tfus | 223.95 | K | N/A | Anonymous, 1942 | Uncertainty assigned by TRC = 0.3 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Tc | 572.2 | K | N/A | Kobe and Mathews, 1970 | Uncertainty assigned by TRC = 0.3 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Pc | 47.08 | atm | N/A | Kobe and Mathews, 1970 | Uncertainty assigned by TRC = 0.1399 atm; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ρc | 3.8124 | mol/l | N/A | Kobe and Mathews, 1970 | Uncertainty assigned by TRC = 0.0056 mol/l; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔvapH° | 8.286 | kcal/mol | N/A | Majer and Svoboda, 1985 | |
ΔvapH° | 9.13 ± 0.26 | kcal/mol | DSC | Rojas-Aguilar, Ginez-Carbajal, et al., 2005 | AC |
ΔvapH° | 8.37 | kcal/mol | N/A | Snelson and Skinner, 1961 | DRB |
ΔvapH° | 8.35 | kcal/mol | V | Cass, Fletcher, et al., 1958 | ALS |
Enthalpy of vaporization
ΔvapH (kcal/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
7.450 | 361. | N/A | Majer and Svoboda, 1985 | |
8.6 | 301. | N/A | Rodríguez, Giner, et al., 2006 | Based on data from 286. to 361. K.; AC |
7.93 | 350. | N/A | Rodriguez, Artigas, et al., 2000 | Based on data from 335. to 412. K.; AC |
8.37 | 288. | A | Stephenson and Malanowski, 1987 | Based on data from 273. to 362. K.; AC |
8.37 | 281. | N/A | Dykyj, 1972 | Based on data from 273. to 288. K. See also Cass, Fletcher, et al., 1958, 2.; AC |
8.5 | 293. | V | Skuratov, Strepikheev, et al., 1957 | Combustion at 293 K; ALS |
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
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -24.69 ± 0.24 | kcal/mol | Chyd | Allinger, Glaser, et al., 1981 | liquid phase; solvent: Hexane |
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:
MM - Michael M. Meot-Ner (Mautner)
LL - Sharon G. Lias and Joel F. Liebman
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
View reactions leading to C5H10O+ (ion structure unspecified)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
IE (evaluated) | 9.25 ± 0.01 | eV | N/A | N/A | L |
Quantity | Value | Units | Method | Reference | Comment |
Proton affinity (review) | 196.7 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 190.1 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Gas basicity at 298K
Gas basicity (review) (kcal/mol) | Reference | Comment |
---|---|---|
191.0 ± 0.02 | Decouzon, Gal, et al., 1996 | T = 338K; MM |
191.0 | Decouzon, Gal, et al., 1996 | T = T(eff) = 430K; MM |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
9.24 ± 0.05 | EI | Holmes and Lossing, 1991 | LL |
9.16 | PE | Behan, Dean, et al., 1976 | LLK |
9.25 ± 0.01 | S | Hernandez, 1963 | RDSH |
9.26 ± 0.03 | PI | Watanabe, Nakayama, et al., 1962 | RDSH |
9.57 | PE | Kimura, Katsumata, et al., 1981 | Vertical value; LLK |
9.46 | PE | Planckaert, Doucet, et al., 1974 | Vertical value; LLK |
9.48 | PE | Kobayashi and Nagakura, 1973 | Vertical value; LLK |
9.50 | PE | Sweigart and Turner, 1972 | Vertical value; LLK |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
C2H4+ | ~13.8 | ? | EI | Collin and Conde-Caprace, 1966 | RDSH |
C2H5O+ | 11.56 | ? | EI | Collin and Conde-Caprace, 1966 | RDSH |
C3H5+ | ~12.8 | ? | EI | Collin and Conde-Caprace, 1966 | RDSH |
C4H7+ | ~12.2 | CH2O+H | EI | Collin and Conde-Caprace, 1966 | RDSH |
C4H8+ | 11.88 | CH2O? | EI | Collin and Conde-Caprace, 1966 | RDSH |
C5H9O+ | 11.22 | H | EI | Collin and Conde-Caprace, 1966 | RDSH |
IR Spectrum
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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: NIST Mass Spectrometry Data Center, William E. Wallace, director
Gas Phase Spectrum
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Additional Data
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Owner | NIST Standard Reference Data Program Collection (C) 2018 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved. |
---|---|
Origin | Sadtler Research Labs Under US-EPA Contract |
State | gas |
References
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Pell and Pilcher, 1965
Pell, A.S.; Pilcher, G.,
Measurements of heats of combustion by flame calorimetry. Part 3.-Ethylene oxide, trimethylene oxide, tetrahydrofuran and tetrahydropy,
Trans. Faraday Soc., 1965, 61, 71-77. [all data]
Snelson and Skinner, 1961
Snelson, A.; Skinner, H.A.,
Heats of combustion: sec-propanol, 1,4-dioxan, 1,3-dioxan and tetrahydropyran,
Trans. Faraday Soc., 1961, 57, 2125-2131. [all data]
Cass, Fletcher, et al., 1958
Cass, R.C.; Fletcher, S.E.; Mortimer, C.T.; Springall, H.D.; White, T.R.,
Heats of combustion and molecular structure. Part V. The mean bond energy term for the C-O bond in ethers, and the structures of some cyclic ethers,
J. Chem. Soc., 1958, 1406-1410. [all data]
Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G.,
Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [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]
Vedal D., 1975
Vedal D.,
Vibrational spectra of pentamethylene sulfide and selenide,
Spectrochim. Acta, 1975, A31, 355-372. [all data]
Skuratov, Strepikheev, et al., 1957
Skuratov, S.M.; Strepikheev, A.A.; Kozina, M.P.,
About the reaction activity of five and six-membered heterocyclic compounds,
Dokl. Akad. Nauk SSSR, 1957, 117, 452-454. [all data]
Inglese, Grolier, et al., 1984
Inglese, A.; Grolier, J.-P.E.; Wilhelm, E.,
Excess volumes and excess heat capacities of oxane + cyclohexane and 1,4-dioxane + cyclohexane,
Fluid Phase Equilibria, 1984, 15, 287-294. [all data]
Inglese, Castagnolo, et al., 1981
Inglese, A.; Castagnolo, M.; Dell'Atti, A.; DeGiglio, A.,
Thermochim. Acta, 1981, 77-87. [all data]
Conti, Gianni, et al., 1976
Conti, G.; Gianni, P.; Matteoli, E.; Mengheri, M.,
Capacita termiche molari di alcuni composti organici mono- e bifunzionali nel liquido puro e in soluzione acquosa a 25C,
Chim. Ind. (Milan), 1976, 58, 225. [all data]
Moelwyn-Hughes and Thorpe, 1964
Moelwyn-Hughes, E.A.; Thorpe, P.L.,
The physical and thermodynamic properties of some associated solutions. II. Heat capacities and compressibilities,
Proc. Roy. Soc. (London), 1964, 278A, 574-587. [all data]
Guieu, Carbonnel, et al., 1985
Guieu, R.; Carbonnel, L.; Kehiaian, H.V.,
Solutions solides organiques I. Etude des diagrammes de phases des systemes oxanne ou 1,4-dioxanne + cyclohexane,
Bull. Soc. Chim. Fr., 1985, 1985, 709. [all data]
Brooks and Pilcher, 1959
Brooks, J.H.; Pilcher, G.,
A Simple Melting Point Calorimeter for Moderately Precise Determination of Purity,
J. Chem. Soc., 1959, 1959, 1535. [all data]
Anonymous, 1942
Anonymous, R.,
, Am. Pet. Inst. Res. Proj. 6, Natl. Bur. Stand., 1942. [all data]
Kobe and Mathews, 1970
Kobe, K.A.; Mathews, J.F.,
Critical Properties and Vapor Pressures of Some Organic Nitrogen and Oxygen Compounds,
J. Chem. Eng. Data, 1970, 15, 182. [all data]
Majer and Svoboda, 1985
Majer, V.; Svoboda, V.,
Enthalpies of Vaporization of Organic Compounds: A Critical Review and Data Compilation, Blackwell Scientific Publications, Oxford, 1985, 300. [all data]
Rojas-Aguilar, Ginez-Carbajal, et al., 2005
Rojas-Aguilar, A.; Ginez-Carbajal, F.; Orozco-Guareno, E.; Flores-Segura, H.,
Measurement of enthalpies of vaporization of volatile heterocyclic compounds by DSC,
J Therm Anal Calorim, 2005, 79, 1, 95-100, https://doi.org/10.1007/s10973-004-0568-3
. [all data]
Rodríguez, Giner, et al., 2006
Rodríguez, S.; Giner, B.; Haro, M.; Martín, S.; Artigas, H.,
Isobaric vapour--liquid equilibrium for the binary systems formed by a cyclic ether and bromocyclohexane at 40.0 and 101.3 kPa,
Physics and Chemistry of Liquids, 2006, 44, 3, 275-285, https://doi.org/10.1080/00319100600574168
. [all data]
Rodriguez, Artigas, et al., 2000
Rodriguez, S.; Artigas, H.; Lafuente, C.; Mainar, A.M.; Royo, F.M.,
Isobaric vapour--liquid equilibrium of binary mixtures of some cyclic ethers with chlorocyclohexane at 40.0 and 101.3 kPa,
Thermochimica Acta, 2000, 362, 1-2, 153-160, https://doi.org/10.1016/S0040-6031(00)00580-3
. [all data]
Stephenson and Malanowski, 1987
Stephenson, Richard M.; Malanowski, Stanislaw,
Handbook of the Thermodynamics of Organic Compounds, 1987, https://doi.org/10.1007/978-94-009-3173-2
. [all data]
Dykyj, 1972
Dykyj, J.,
Petrochemia, 1972, 12, 1, 13. [all data]
Cass, Fletcher, et al., 1958, 2
Cass, R.C.; Fletcher, S.E.; Mortimer, C.T.; Quincey, P.G.; Springall, H.D.,
193. Heats of combustion and molecular structure. Part IV. Aliphatic nitroalkanes and nitric esters,
J. Chem. Soc., 1958, 958, https://doi.org/10.1039/jr9580000958
. [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]
Decouzon, Gal, et al., 1996
Decouzon, M.; Gal, J.E.; Herreros, M.; Marai, P.C.; Murrell, J.; Todd, J.F.J.,
On the Use of the Kinetic Method for the Determination of Proton Affinities by Fourier-Transfrom Ion Cyclotron Resonance Mass Spectrometry,
Rapid. Comm. Mass Spectrom., 1996, 10, 242. [all data]
Holmes and Lossing, 1991
Holmes, J.L.; Lossing, F.P.,
Ionization energies of homologous organic compounds and correlation with molecular size,
Org. Mass Spectrom., 1991, 26, 537. [all data]
Behan, Dean, et al., 1976
Behan, J.M.; Dean, F.M.; Johnstone, R.A.W.,
Photoelectron spectra of cyclic aromatic ethers. The question of the Mills-Nixon effect,
Tetrahedron, 1976, 32, 167. [all data]
Hernandez, 1963
Hernandez, G.J.,
Vacuum-ultraviolet absorption spectra of the cyclic ethers: trimethylene oxide, tetrahydrofuran, and tetrahydropyran,
J. Chem. Phys., 1963, 38, 2233. [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]
Kimura, Katsumata, et al., 1981
Kimura, K.; Katsumata, S.; Achiba, Y.; Yamazaki, T.; Iwata, S.,
Ionization energies, Ab initio assignments, and valence electronic structure for 200 molecules
in Handbook of HeI Photoelectron Spectra of Fundamental Organic Compounds, Japan Scientific Soc. Press, Tokyo, 1981. [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]
Kobayashi and Nagakura, 1973
Kobayashi, T.; Nagakura, S.,
Photoelectron spectra of tetrahydropyran, 1,3-dioxane, and 1,4-dioxane,
Bull. Chem. Soc. Jpn., 1973, 46, 1558. [all data]
Sweigart and Turner, 1972
Sweigart, D.A.; Turner, D.W.,
Lone pair orbitals and their interactions studied by photoelectron spectroscopy. II. Equivalent orbitals in saturated oxygen and sulfur J. Heterocycl. Chem.,
J. Am. Chem. Soc., 1972, 94, 5599. [all data]
Collin and Conde-Caprace, 1966
Collin, J.E.; Conde-Caprace, G.,
Ionization and dissociation of cyclic ethers by electron impact,
Intern. J. Mass Spectrom. Ion Phys., 1966, 1, 213. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, References
- Symbols used in this document:
AE Appearance energy Cp,gas Constant pressure heat capacity of gas Cp,liquid Constant pressure heat capacity of liquid IE (evaluated) Recommended ionization energy Pc Critical pressure Tboil Boiling point Tc Critical temperature Tfus Fusion (melting) point ΔcH°gas Enthalpy of combustion of gas at standard conditions 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 ΔvapH Enthalpy of vaporization ΔvapH° Enthalpy of vaporization at standard conditions ρc Critical density - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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