Process for the preparation of stilbenedicarboxylate derivatives
AssigneeEastman Kodak Company
InventorsDale E. Van Sickle, John C. Morris, Marvin A. McCall, Jean C. Fleischer, Ted R. Walker, Jr.
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Abstract
Disclosed is a process for producing dimethyl or novel diphenyl derivatives of stilbenedicarboxylic acids from dimethyl toluates or diphenyl toluates and sulfur. The reaction requires an excess of toluate to sulfur of at least about 5:1. In addition hydrogen sulfide is removed from the reaction zone.
Claims25
A process for preparation of an ester compound of the formula:
- ##STR3## wherein R is bonded at the meta or para positions, and is a group of the formula --COOR' wherein R' is methyl or phenyl,
- comprising reacting a compound of the formula:
- ##STR4## wherein R is as defined hereinabove, with elemental sulfur, wherein Compound II is initially present at a molar excess relative to sulphur of at least about 5:1, and hydrogen sulfide produced during the reaction is removed from the reaction zone, said process occurring under an inert atmosphere and under reaction conditions such that Compound I is formed.
A process for forming an ester compound of the formula:
- ##STR5## wherein R is bonded at the meta or para positions, and is a group of the formula --COOR' wherein R' is methyl or phenyl, comprising reacting an appropriate dimethyl bibenzyldicarboxylate derivative or a diphenyl bibenzyldicarboxylate derivative with elemental sulfur in the presence of a suitable solvent under reaction conditions such that Compound I is formed.
A process for purifying a para or meta diphenyl ester derivative of stilbenedicarboxylic acid from a reaction product containing a dimethyl ester stilbene derivative starting material, diphenyl acetate, a catalyst and reaction by-products comprising recrystallizing said reaction product using an appropriate solvent containing dimethylformamide.
Dependencies are inferred from the claim text.