ABSTRACT

Vapor pressures of 1-(n-alkyl)-benzimidazoles with chain lengths from methyl to pentyl (C1 C5) have been determined as a function of temperature by the transpiration method. From these data, the molar enthalpies of vaporization (?1gHm) were calculated, and a linear correlation with the number of carbon atoms was found. At a given temperature, 1-n-alkylbenzimidazole vapor pressures were found to decrease with the increasing length of alkyl chain, and the fused ring system was found to lower vapor pressures and increase heats of vaporization relative to the corresponding 1-n-alkylimidazoles.

Compounds

#	Formula	Name
1	C8H8N2	1-methylbenzimidazole
2	C9H10N2	1-ethyl-1H-benzimidazole
3	C10H12N2	1-propyl-1H-benzimidazole
4	C11H14N2	1-butyl-1H-benzimidazole
5	C12H16N2	1-pentyl-1H-benzimidazole

Datasets

The table above is generated from the ThermoML associated json file (link above). POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied; the numbers refer to the table of compounds on the left.
Type	Compound-#	Property	Variable	Phase	Method	#Points
POMD	1	Normal melting temperature, K ; Crystal		Crystal Liquid Air at 1 atmosphere	DTA	1
POMD	1	Molar enthalpy of transition or fusion, kJ/mol ; Crystal		Crystal Liquid Air at 1 atmosphere	DSC	1
POMD	1	Vapor or sublimation pressure, kPa ; Crystal	Temperature, K; Crystal	Crystal Gas	Transpiration method	13
POMD	1	Vapor or sublimation pressure, kPa ; Liquid	Temperature, K; Liquid	Liquid Gas	Transpiration method	30
POMD	2	Vapor or sublimation pressure, kPa ; Liquid	Temperature, K; Liquid	Liquid Gas	Transpiration method	19
POMD	3	Vapor or sublimation pressure, kPa ; Liquid	Temperature, K; Liquid	Liquid Gas	Transpiration method	21
POMD	4	Vapor or sublimation pressure, kPa ; Liquid	Temperature, K; Liquid	Liquid Gas	Transpiration method	23
POMD	5	Vapor or sublimation pressure, kPa ; Liquid	Temperature, K; Liquid	Liquid Gas	Transpiration method	24

Thermodynamics Research Center / ThermoML | Journal of Chemical and Engineering Data

Building Blocks for Ionic Liquids: Vapor Pressures and Vaporization Enthalpies of 1-(n-Alkyl)-benzimidazoles

Garist, I. V., Verevkin, S. P.[Sergey P.]

ABSTRACT