Synthesis, characterization and thermochemical properties of N-acyl-N ',N '-diethylthioureas

• Type: Article in International Scientific Journal
• Date: 2001

Authors

da Silva, MAVR (Author) FCUP; da Silva, MDMCR (Author) FCUP; da Silva, LCM (Author) Other; Dietze, F (Author) Other; Hoyer, E (Author) Other; Beyer, L (Author) Other; Schroder, B (Author) Other; Damas, AM (Author) ICBAS; Liebman, JF (Author) Other

Journal

The Journal is awaiting validation by the Administrative Services.

Title: Journal of the Chemical Society. Perkin Transactions 2

Pages: 2174-2178

ISSN: 0300-9580

Indexing

ISI Web of Knowledge - 13 Citations

Scopus - 13 Citations

Scientific classification

FOS: Natural sciences > Chemical sciences

Other information

Authenticus ID: P-000-SXZ

DOI: 10.1039/b104709b

Abstract (EN): Three N-acyl-N',N'-diethylthioureas, RCONHCSNEt2. R = Pr-1, Bu-1, Bu-1, have been prepared and characterised. The standard (p(o) = 0.1 MPa) molar enthalpies of combustion in oxygen of the three crystalline compounds, at T = 298.15 K. have been measured by rotating bomb-combustion calorimetry. and the standard molar enthalpies of sublimation of the compounds by microcalorimetry. These values were used to derive the standard molar enthalpies of formation of the compounds in their crystalline and gaseous phases, respectively. The derived standard molar enthalpies of formation in the gaseous state are discussed comparatively. Acid constants and some complex stabilities have been measured pH-potentiometrically in dioxane-water mixture. The crystal structure of N,N-diethyl-N'-isovaleroyl-thiourea is presented and shows a delocalization of the pi electrons of the C=S group over the carbon-amine nitrogen bond. CS-NEt2 stabilising the molecule, in accordance with the thermochemical results.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 5