Bis-Heteronucleophilic Michael Addition to Divinyl Sulfone: A New Efficient Access to Macrocycles
摘要:
The Michael addition of bis(nitrogen or sulfur) nucleophiles to divinyl sulfone provides the corresponding macrocyclic adducts in good yields. The structures of some new macrocyclic sulfones are established by X-ray crystallographic analysis and NMR spectroscopy. The subsequent cleavage of benzyl or tosyl groups yields the unprotected macrocyclic sulfones.
Bis-Heteronucleophilic Michael Addition to Divinyl Sulfone: A New Efficient Access to Macrocycles
摘要:
The Michael addition of bis(nitrogen or sulfur) nucleophiles to divinyl sulfone provides the corresponding macrocyclic adducts in good yields. The structures of some new macrocyclic sulfones are established by X-ray crystallographic analysis and NMR spectroscopy. The subsequent cleavage of benzyl or tosyl groups yields the unprotected macrocyclic sulfones.
Decolorizable ink composition and ink jet printer using the ink composition
申请人:Ricoh Company, Ltd.
公开号:EP1149877A1
公开(公告)日:2001-10-31
In an ink composition, a coloring agent, a color developer, and a decolorization agent are dissolved or dispersed in a solvent. The ink is capable of being colored at 40°C or less, with the coloring agent reacting with the color developer to form a bonded structure, and also capable of being decolorized when heated to 100°C or more, with the bonded structure being ruptured to liberate the color developer therefrom, and the liberated color developer being chemically bonded to the decolorization agent. An ink jet printer is provided with a paper feeder for feeding a recording sheet for ink jet printing, a recorder for recording an ink image on the recording sheet fed from the paper feeder using the above-mentioned ink composition, and a paper discharger for discharging the recording sheet from the ink jet printer. By further providing an eraser, the ink image recorded on the recording sheet by the recorder can be erased, thereby achieving recycling of the recording sheet.
The Michael addition of bis(nitrogen or sulfur) nucleophiles to divinyl sulfone provides the corresponding macrocyclic adducts in good yields. The structures of some new macrocyclic sulfones are established by X-ray crystallographic analysis and NMR spectroscopy. The subsequent cleavage of benzyl or tosyl groups yields the unprotected macrocyclic sulfones.