Water soluble, synthesis using

Epoxides are possibly the most studied of the three-membered heterocycles. While a host methods for the synthesis of epoxides have been developed, work continues, especially in the development of more chemo-, regio-, and stereoselective methods. The development of new metal-based epoxidation catalysts continues to garner significant levels of activity. The use of the Mn-based catalyst, I, with a water-soluble ligand provides excellent yields of the corresponding epoxides <06MI139>. A Mn-salen complex was modified by the addition of phosphonium groups at either end to render it water-soluble. The use of 5 mol% of this catalyst with NalO as the oxidant provided a quantitative yield of cyclohexene oxide from cyclohexene. 

Ryu EH, Zhao Y (2005) Efficient synthesis of water-soluble calixarenes using click chemistry. Org Lett 7 1035-1037... 

Scheme 26. Synthesis of water-soluble dendrimers used for transfection experiments...

However, the use of water-soluble monomer in emulsion polymerization is more complicated. A potential example is the synthesis of thermally sensitive magnetic microspheres using water-soluble NIPAM, using the combination of emulsion polymerization and then seeded precipitation polymerization [140, 141], Lee et al. [140] conducted the synthesis of magnetic latex by a two-stage process at the first... 

Each of the products whose synthesis is illustrated in Schemes 6.2 and 6.3 is a coloured cationic species. When the counteranion is chloride, the products are water-soluble and useful as basic (cationic) dyes for the eoloration of acrylic fibres. Precipitation of cationic dyes of these types from aqueous solution using large polymeric counteranions, notably phosphomolybdates, phosphotungstates and phos-phomolybdotungstates, leads to a range of highly insoluble red. 

The various commercial water-soluble polymers used for the synthesis of polypyrrole colloids are rather ineffective for the preparation of sterically stabilized polyaniline colloids and usually fail to prevent macroscopic precipitation [46]. One exception to this rule is poly(vinyl alcohol), but even here a relatively high stabilizer concentration is required for the quantitative formation... 

Pyrrohdinone (2-pyrrohdone, butyrolactam or 2-Pyrol) (27) was first reported in 1889 as a product of the dehydration of 4-aminobutanoic acid (49). The synthesis used for commercial manufacture, ie, condensation of butyrolactone with ammonia at high temperatures, was first described in 1936 (50). Other synthetic routes include carbon monoxide insertion into allylamine (51,52), hydrolytic hydrogenation of succinonitnle (53,54), and hydrogenation of ammoniacal solutions of maleic or succinic acids (55—57). Properties of 2-pyrrohdinone are Hsted in Table 2. 2-Pyrrohdinone is completely miscible with water, lower alcohols, lower ketones, ether, ethyl acetate, chloroform, and benzene. It is soluble to ca 1 wt % in aUphatic hydrocarbons. 

By use of a modification of the well-known Williamson synthesis it is possible to prepare a number of cellulose ethers. Of these materials ethyl cellulose has found a small limited applieation as a moulding material and somewhat greater use for surfaee eoatings. The now obsolete benzyl cellulose was used prior to World War II as a moulding material whilst methyl eellulose, hyroxyethyl eellulose and sodium earboxymethyl eellulose are useful water-soluble polymers. 

Interest in the chemistry of water-soluble polymers (polyelectrolytes) has been continually increasing during the past 45 years. The tremendous scope of utility for water-soluble polymers has led to a vigorous search for new materials and the rapid development of polyelectrolytes into a dynamic field of industrial research. Growth in this field has been especially rapid since 1960 and today, many companies are engaged in synthesis and applications research on polyelectrolytes that are primarily used in four main marketing areas water treatment, paper, textiles, and oil recovery [1]. Polyacrylamide gel was also used as soil conditioner [2-4]. 

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