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Pendant alcohol groups

In an analogous manner, propargyl vinyl ethers with a pendant alcohol group as internal nucleophile gave 5,6- or 6,6-spiroketals with excellent diastereoselectivity (Scheme 4-49). This transformation is an example for efficient center-to-axis-to-center chirality transfer. [Pg.468]

In 2007, Cao and Jana at Akron tethered Cloisite 30B clay particles onto SMP polyurethanes [70]. The polyurethanes were synthesized from aromatic diisocyanates, a crystalline polyester polyol, and poly(e-caprolactone) (PCL) diol. The monomer ratios were cleverly balanced between an excess ratio of isocyanate in the polymer system and the pendant alcohol groups (-CH2CH2OH) on the quaternary ammonium ions fi om the Cloisite 30B. The team observed an increase in the rubbery modulus at 100°C (Tm-I- 50°C) of nearly one order of magnitude, from 4—5 MPa without loading to more than 20 MPa with loading. In the carefully crafted study, the authors determined that at high (5%) clay content, a more rapid relaxation of induced tensile stress reduces the recovery force of SMPs. In addition,... [Pg.327]

Figure 4 Section of the crystal structure of [Znfbtpjfdpedjj]. Only one disorder position is shown for each bridging ligand for the sake of clarity. The pendant alcohol groups directed into the MOF cavities can form R-O-M bonds with M = Li(I) and Mg(II)>o... Figure 4 Section of the crystal structure of [Znfbtpjfdpedjj]. Only one disorder position is shown for each bridging ligand for the sake of clarity. The pendant alcohol groups directed into the MOF cavities can form R-O-M bonds with M = Li(I) and Mg(II)>o...
In the presence of cationic initiators, the possibiUty for loss of pendant ether groups to form free alcohol is another side reaction that usually results in color formation because of the highly conjugated products formed. [Pg.515]

The solubility parameter is about 19.2MPa and being amorphous they dissolve in such solvents as tetrahydrofuran, mesityl oxide, diacetone alcohol and dioxane. Since the main chain is composed of stable C—C and C—O—C linkages the polymer is relatively stable to chemical attack, particularly from acids and alkalis. As already mentioned, the pendant hydroxyl groups are reactive and provide a site for cross-linking. [Pg.607]

The pendant hydroxy groups of ethylene oxide-propylene oxide copolymers of dihydroxy and trihydroxy alcohols may be sulfurized to obtain a sulfurized alcohol additive. This is effective as a lubricant in combination with oils and fats [387,533]. The sulfurized alcohols may be obtained by the reaction of sulfur with an unsaturated alcohol. Furthermore, fatty alcohols and their mixtures with carboxylic acid esters as lubricant components [1286] have been proposed. [Pg.14]

Poly(vinyl alcohol) (PVA) is a polymer of great interest because of its many desirable characteristics specifically for various pharmaceutical, biomedical, and separation applications. PVA has a relatively simple chemical structure with a pendant hydroxyl group (figure la). The monomer, vinyl alcohol, does not exist in a stable form, rearranging to its tautomer, acetaldehyde. Therefore, PVA is produced by the polymerization of vinyl acetate to poly(vinyl acetate) (PVAc) followed by the hydrolysis to PVA (figure 2). Once the hydrolysis reaction is not complete, there are PVA with different degrees of hydrolysis (figure lb). For practical purposes, PVA is always a co-polymer of vinyl alcohol and vinyl acetate [1]. [Pg.119]

Connon and co-workers [137,147] also set out to develop a chiral catalyst which operates via an induced-fit mechanism. Derived from a 3-substituted 4-PPY and possessing a pendant aromatic group, this new catalyst (41, Fig. 7) allowed moderate to good selectivities to be achieved for a wide range of aryl alkyl i cc-alcohols. Connon [148] later showed that small improvements in selectivity could be obtained by introducing electron-deficient aryl groups. Finally, he was able to expand the substrate scope to include ec-alcohols obtained by Baylis-Hilhnan reaction [148]. [Pg.255]

Those containing pendant functional groups and only carbon atoms in the main chain (polyvinyl alcohol). [Pg.90]

Polymerizable dyes were synthesized by reacting chromophores bearing pendant primary alcohol groups with acryloyl chloride or methacryloyl chloride (Figure 5). [Pg.285]

Regarding polyesters, Russell and coworkers reported the lipase (Novo-zyme-435)-catalyzed polycondensation of various triols and divinyl adipate for the synthesis of polyesters having pendant hydroxy groups (Scheme 28) [109]. Before this report, the divinyl adipate was reported to be available for enzymatic polyesterification of diols by Kobayashi and coworkers [110,111], in which the equilibrium of esterification is shifted in the forward direction by tautomerization of the eliminated vinyl alcohol to acetaldehyde. The Mw values of the resulting polyesters varied according to the triol used and ranged from 3000 to 14 000. Analysis by MALDI-TOF mass... [Pg.21]

Polymers with pendant carbodiimide groups 27 are also synthesized from crossUnked polystyrene. In this synthetic route crossUnked polystyrene beads are chloromethylated and converted to the amines. Reaction with isopropyl isocyanate gives the corresponding ureas, which are treated with tosyl chloride and triethylamine to produce the crossUnked polycarbodiimides. This polymer is used in the polymer supported Moffatt oxidation of alcohols into aldehydes or ketones using benzene/DMSO. ... [Pg.250]

Various TTF-pendant groups were attached on the surface of the dendrimer 786 by esterification of the corresponding carboxylic acid 785 with the dendrimer 784 bearing 12 outer alcohol groups using the dicyclo-hexylcarbodiimide (DCC)-DMAP system (Scheme 116) <20040L2109>. [Pg.1048]


See other pages where Pendant alcohol groups is mentioned: [Pg.75]    [Pg.388]    [Pg.103]    [Pg.794]    [Pg.247]    [Pg.349]    [Pg.68]    [Pg.75]    [Pg.388]    [Pg.103]    [Pg.794]    [Pg.247]    [Pg.349]    [Pg.68]    [Pg.186]    [Pg.712]    [Pg.53]    [Pg.66]    [Pg.66]    [Pg.100]    [Pg.126]    [Pg.282]    [Pg.119]    [Pg.90]    [Pg.23]    [Pg.702]    [Pg.172]    [Pg.16]    [Pg.65]    [Pg.263]    [Pg.387]    [Pg.124]    [Pg.158]    [Pg.54]    [Pg.54]    [Pg.77]    [Pg.106]    [Pg.284]    [Pg.254]    [Pg.1038]    [Pg.1087]    [Pg.1322]   
See also in sourсe #XX -- [ Pg.75 ]




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Alcohol groups

Alcoholic groups

Pendant group

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