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Sacrificial spacer approach

Caution Carry out all procedures in a well-ventilated fume-cupboard, wear appropriate protective gloves, a lab-coat, and safety glasses. All vacuum-line work should be performed while behind a protective blast-proof screen. Check all glassware for star cracks before using under vacuum and never use flat-bottomed flasks with rotary evaporators. [Pg.203]

Preparation of 4-vinylphenol This method was based on that originally published by Corson et al.  [Pg.204]

Dissolve 8.6 g of potassium hydroxide (8.6 g, 153 mol) in distilled water (85 ml) in a 250 ml conical flask, cool to room temperature. [Pg.204]

Add THF (1 ml) and 4-acetoxystyrene (10 g, 62 mmol). Vigorously stir the reaction mixture at room temperature until the oily layer has completely dissolved in the aqueous part (approximately 1 h). [Pg.204]

Filter the solution into a clean 250 mL flask and stand in an ice-bath. [Pg.204]


Fig. 7.3. Synthesis of polymeric receptors for TCDD by a modified sacrificial spacer approach using the urea monomer (7). DVB = divinylbenzene. Adapted from [23],... Fig. 7.3. Synthesis of polymeric receptors for TCDD by a modified sacrificial spacer approach using the urea monomer (7). DVB = divinylbenzene. Adapted from [23],...
Scheme 2 The preparation of polymers by the sacrificial spacer approach imprinted against (a) cholesterol and (b) pyridine. Scheme 2 The preparation of polymers by the sacrificial spacer approach imprinted against (a) cholesterol and (b) pyridine.
The cavity left behind after cleaving off the covalently bound template moiety is often too small to accommodate the target molecule during non-covalent rebinding. This problem was addressed by Whitcombe in 1994 when the sacrificial spacer approach was introduced [72]. In this approach, the template and the monomer is joined by a spacer, which is cleaved off when the template is cleaved from the polymer (Figure 2.3). The sacrificial spacer approach has been applied to the imprinting of cholesterol [73], DDT [74] and heterocyclic aromatic compounds [75]. [Pg.19]

Figure 2.3 Semi-covalent molecular imprinting of cholesterol using the sacrificial spacer approach. Polymerization (1) cleavage and extraction (2) rebinding (association) (3) and dissociation (4). Figure 2.3 Semi-covalent molecular imprinting of cholesterol using the sacrificial spacer approach. Polymerization (1) cleavage and extraction (2) rebinding (association) (3) and dissociation (4).
The semi-covalent" and sacrificial spacer approaches of imprinting bear similarities to the covalent imprinting approach, at least in the imprinting step, where the template is covalently bound to the functional monomer. In the latter approach, labile covalent bonds, such as carbonates... [Pg.2594]

Figure 17 Schematic view of the imprinting of cholesterol nsing a semicovalent, sacrificial spacer approach. Figure 17 Schematic view of the imprinting of cholesterol nsing a semicovalent, sacrificial spacer approach.
The role of sacrificial spacer can also be filled by larger species, for example, salicylic acid. This approach is particularly useful in the imprinting of amine templates, as demonstrated by the model compound 30 (Fig. 19). This was prepared by the reaction... [Pg.107]

An approach taken to overcome these deficiencies is the use of the so-called sacrificial spacers [29]. In this method the intermediate species used during the pre-polymerization of the MIP to link the monomers and the template is chosen so that it is eliminated—or in other words sacrificed—during the removal of the template. This way not only is the template attached to the monomer, the chances of steric influences of the residual moe-ities during the future rebindings with the target species are also avoided. Instances of the common sacrificial intermediate species are spacers with carbonyl groups [59-70] or the less frequent instances of salicylate (2-hydroxybenzoate) [60,71], dimethyl silyl group of silyl ethers [72] and silyl esters [73]. [Pg.273]


See other pages where Sacrificial spacer approach is mentioned: [Pg.171]    [Pg.183]    [Pg.204]    [Pg.211]    [Pg.1739]    [Pg.203]    [Pg.203]    [Pg.214]    [Pg.120]    [Pg.171]    [Pg.183]    [Pg.204]    [Pg.211]    [Pg.1739]    [Pg.203]    [Pg.203]    [Pg.214]    [Pg.120]    [Pg.13]    [Pg.204]    [Pg.206]    [Pg.209]    [Pg.211]    [Pg.110]    [Pg.120]    [Pg.585]   
See also in sourсe #XX -- [ Pg.19 , Pg.20 ]

See also in sourсe #XX -- [ Pg.214 ]

See also in sourсe #XX -- [ Pg.99 , Pg.120 ]




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