Divinylsulfone

R. S. Kohn. Thixotropic aqueous solutions containing a divinylsulfone-crosslinked polygalactomannan gum. Patent US 4752339, 1988. 

Divinyl sulfide, 25 630 Divinylsulfone method, for covalent ligand immobilization, 6 3961 Division of Chemical Nomenclature and Structure Representation (IUPAC),... 

Cyanogen bromide method A,A -Carbonyl diimidazole method Divinylsulfone method Epoxy (bisoxirane) method Ethyldimethylaminopropyl carbodiimide method Eluoromethylpyridinium toluenesulfonate method A-hydroxysuccinimide ester method Schiff base (reductive amination) method Tresyl chloride/tosyl chloride method Sulfhydryls Azalactone method (for azalactone supports)... 

Divinylsulfone method Epoxy (bisoxirane) method lodoacetyl/bromoacetyl mediods Maleimide method Pyridyl disulfide method TNB-thiol method... 

A higher degree of divinylsulfone crosslinking was observed in the comparative sample because of the absence of O-methylation of a-cyclodextrin polyrotaxane. 

An attractive synthesis of cyclobutanones involves the titanium(IV) chloride catalyzed cycloaddition of mixed ketene acetals 46 with divinylsulfone (49) used as an ethene equivalent, The primary 2-vinylsulfonylcyclobutanones 50 formed can be desulfonylated to the corresponding cyclobutanones 51 in the presence of an aluminum amalgam.20... 

Caution Divinylsulfone is highly toxic, and the column preparation procedures should be carried out m a well-ventilated hood. 

Add 10 mL of divinylsulfone dropwise over a period of 15 mm with constant stirring. After addition is complete, slowly stir the gel suspension for 1 h at room temperature. 

Immobilized ligands prepared by the divinylsulfone method are unstable above pH 8.0. 

It may be added that polymers of related structures can be obtained by substituting either bis-(acrylic esters), or divinylsulfone, for bis-acrylamides 45>, or hydrazines 46) for amines. Some of these polymers are listed in Table 1. 

Addition of NH- and N-vinylpyrroles to electrophilic alkenes Pyrroles 100 readily added to divinylsulfone in the presence of catalytic amounts of MOH to afford selectively di[2-(pyrrol-l-yl)ethyl]sulfones (101) (Equation (25)) (99ZOR1226). 

The use of bifunctional cross-linking reagents, such as divinylsulfone, leads to the additional covalent bonding of oxidized starch molecules. This allows a further increase in the water-absorbing properties. Thus, ecologically problematic oxidants such as bleach or NO2 are becoming obsolete [24]. 

Table 27. Effect of polymer type on transition temperature and sharpness of transition of gels crosslinked with divinylsulfone [163]...

Divinylsulfone Activation. One-half gram of IV-acetylated heparin was dissolved in 10 mL of 1.0M Na2C03 solution. One milliliter of divinylsulfone and either 1 mL of n-butylamine or 1 g of glycine or 2-aminoethyl hydrogen sulfate were added to the heparin solutions which were allowed to react at 22°C for 3 h. The reaction schemes are illustrated in Figure 3. The hydroxyl-derivatized heparins were then dialyzed and freeze-dried. 

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