PRODUCTION OF ETHENE DERIVATIVE

摘要

PURPOSE:To obtain a 1,1-bis-(dialkylaminophenyl)ethene derivative useful as an intermediate for long wavelength absorbing leuco dye, by dehydrating an alcohol derivative in an organic solvent in the presence of an anhydrous inorganic sulfate as a dehydrating auxiliary. CONSTITUTION:A compound shown by formula I (R1-R4 are lower alkyl; R5 is H or lower alkyl) is reacted in an organic solvent (e.g. diethyl ether of THF) in the presence of an anhydrous inorganic sulfate (e.g. anhydrous sodium sulfate or anhydrous magnesium sulfate) at normal temperature or under heating for several hours to give a compound shown by formula II in high purity and in high yield. The amount of the anhydrous inorganic sulfate used is preferably 2-4mol. based on 1mol. compound shown by formula I.