Jean Fournier

Functional carbonates: cyclic α-methylene and β-oxopropyl carbonates from prop-2-ynyl alcohol derivatives and CO2

The phosphine-catalysed synthesis of cyclic α-methylene carbonates 2 directly from prop-2-ynyl alcohol derivatives and CO2 is described. These cyclic carbonates 2 are key intermediates for the selective access to β-oxopropyl carbonates 3 by reaction with alcohols under mild conditions, but in the presence of Et2N or KCN as catalyst.

Measurement of mercurous chloride vapor pressure

The composition of mercurous chloride vapor is not well known despite the studies devoted to it. This paper is a study of calomel vapor pressure based on atomic absorption spectroscopy of mercury in the vapor phase. The results obtained prove that in the vapor phase below 473 K, mercurous chloride is completely dissociated into mercury and mercuric chloride, and resultant vapor pressure measurements correspond closely to those obtained with the Knudsen effusion method.

MERCUROUS CHLORIDE VAPOR PHASE TRANSPORT

With a model for transporting vapor phase calomel in a sealed ampoule at the temperature of 473 K, taking into account the dissociation of calomel (Hg2Cl2s ⇆ HgCl2g +Hgg), a possible excess of mercury chloride and residual gases, is presented. A unidimensional geometry following the O x axis model in a horizontal cylinder closed ampoule in a two-zone furnace system has been developed. Theoretical versus experimental results are compared. For a sink temperature lower than 393 K the experimental and calculated mass fluxes diverge with a binary mixture and are close to one another with a ternary mixture.

Study of Mercurous Chloride Crystal Growth

In this work we deal with the mercurous chloride (Hg 2 Cl 2 ) or calomel crystal growth in vapour phase by flux forced method, taking into account the total dissociation of calomel in mercury and mercuric chloride. The concentrations of mercury and mercuric chloride along the growth ampoule depend on the matter transport model from the source to sink. We use a molecular diffusion model of mercury and mercuric chloride through an immobile inert gas. The attempts of growth showed the key role of the concentrations of mercury and mercuric chloride as well as their ratio at the maximum of supersaturation.