Acid derivative, acrylic

Acrylic acid derivatives. Acrylic esters polymerise readily under the influence of oxygen, peroxides, light or heat to give colourless, glass-Uke plastics. 

Apart from the thoroughly studied aqueous Diels-Alder reaction, a limited number of other transformations have been reported to benefit considerably from the use of water. These include the aldol condensation , the benzoin condensation , the Baylis-Hillman reaction (tertiary-amine catalysed coupling of aldehydes with acrylic acid derivatives) and pericyclic reactions like the 1,3-dipolar cycloaddition and the Qaisen rearrangement (see below). These reactions have one thing in common a negative volume of activation. This observation has tempted many authors to propose hydrophobic effects as primary cause of ftie observed rate enhancements. 

Table 1. Physical Properties of Acrylic Acid Derivatives...

In the case of electron-deficient monomers (e.g, acrylics) it is accepted that reaction occurs by initial addition of the sulfate radical anion to the monomer. Reactions of sulfate radical anion with acrylic acid derivatives have been shown to give rise to the sulfate adduct under neutral or basic conditions but under acidic conditions give the radical cation probahly by an addition-elimination process. 

In recent years, the catalytic asymmetric hydrogenation of a-acylamino acrylic or cinnamic acid derivatives has been widely investigated as a method for preparing chiral a-amino acids, and considerable efforts have been devoted for developing new chiral ligands and complexes to this end. In this context, simple chiral phosphinous amides as well as chiral bis(aminophosphanes) have found notorious applications as ligands in Rh(I) complexes, which have been used in the asymmetric hydrogenation of a-acylamino acrylic acid derivatives (Scheme 43). 

Table 2 Enantioselective hydrogenation of a-acylamino acrylic acid derivatives...

Scheme 8.19 Hydrogenations of acrylic acid derivatives with sugar dithioether ligands.

Grafting of Acrylic Acid Derivatives onto Polyethylene and Polypropylene Surfaces... 

Acrylic acid derivatives/esters Carboxymethyl cellulose (CMC)... 

The tetracyclic /3-carboline derivatives 452-454 have been prepared as sleep disorder therapeutics. The synthesis (Scheme 100) involves the reaction between the enamino ester 451 and acrylic acid derivatives, activated in certain cases with ethyl chloroformate <1997TL8475>. 

Enantioselective Diels-Alder reactions proceed smoothly in the presence of a chiral Sc catalyst, prepared in situ from Sc(OTf)3, R)- I )-l,l -bi-2-napluhol [(R)-BINOL], and a tertiary amine in dichloromethane.58 The catalyst is also effective in Diels-Alder reactions of an acrylic acid derivative with dienes (Scheme 14). 

Kusonwiriyawong C, van de Wetering P, Hubbell JA et al (2003) Evaluation of pH-dependent membrane-disruptive properties of poly(acrylic acid) derived polymers. Eur J Pharm Biopharm 56 237-246... 

Many polymers have been studied for their usefulness in producing pharmacologically active complexes with proteins or drugs. Synthetic and natural polymers such as polysaccharides, poly(L-lysine) and other poly(amino acids), poly(vinyl alcohols), polyvinylpyrrolidinones, poly(acrylic acid) derivatives, various polyurethanes, and polyphosphazenes have been coupled to with a diversity of substances to explore their properties (Duncan and Kopecek, 1984 Braatz et al., 1993). Copolymer preparations of two monomers also have been tried (Nathan et al., 1993). 

Compared with 3-alkyl-3-(acylamino)acrylic acid derivatives, much less success has been obtained in the asymmetric hydrogenation of 3-aryl-3-(acylamino)acrylic acid derivatives. An Et-FerroTANE-Rh catalyst has provided up to 99% ee for the hydrogenation of a series of (E)-3-aryl-3-(acylamino)acrylates.95 Since (E)-3-aryl-3-(acylamino)-acrylic acid derivatives are difficult to obtain in large scales compared to (Z)-3-aryl-3-(acylamino)acrylic acid... 

Alkylation of norbornene with acrylic acid derivatives occurs with ruthenium catalysts like [RuCl2(C6H6)]2/Zn in protic solvent.31 (,E)-o -2-norbonylacrylates are obtained with high regio- and stereoselectivity in good yields. 

Although a cobalt-catalyzed intermolecular reductive aldol reaction (generation of cobalt enolates by hydrometal-lation of acrylic acid derivatives and subsequent reactions with carbonyl compounds) was first described in 1989, low diastereoselectivity has been problematic.3 6 However, the intramolecular version of this process was found to show high diastereoselectivity (Equation (37)).377,377a 378 A Co(i)-Co(m) catalytic cycle is suggested on the basis of deuterium-labeling studies and the chemistry of Co(ll) complexes (Scheme 81). Cobalt(m) hydride 182, which is... 

Quantitative rate measurements under a variety of conditions support such a mechanism [4, 15]. A complete kinetic analysis is available for the hydrogenation of acrylic acid derivatives using the precatalysts RuCl2(PPh3)3 in the solvent dimethylacetamide, although the system is much less active in this more polar and coordinating solvent (e.g., entry 3, Table 3.1). 

Table 21.11 Directive hydrogenation of acrylic acid derivatives. 

The enantioselective hydrogenation of a,fj- or / ,y-unsaturated acid derivatives and ester substrates including itaconic acids, acrylic acid derivatives, buteno-lides, and dehydrojasmonates, is a practical and efficient methodology for accessing, amongst others, chiral acids, chiral a-hydroxy acids, chiral lactones and chiral amides. These are of particular importance across the pharmaceutical and the flavors and fragrances industries. 

The starting materials used for the catalytic versions are much more expensive US 20-25 kg-1 for the vinyl and US 50 kg-1 for the acrylic acid derivative, compared to ca. US 10 kg 1 for methoxybromonaphthalene used in the Syntex process. 

U.S. producers and capacities, 2 361t vapor pressure of important, 2 346t Acrylic acid derivatives, 2 342-369 analysis, 2 361-362 economic aspects, 2 361... 

The application of chiral boron catalysts in the cycloadditions of ,/3-unsaturated aldehydes and acrylic acid derivatives has been investigated most. 

The failure in increasing residence time of mucoadhesive systems in the human intestinal tract has led scientists to the evaluation of multifunctional mucoadhesive polymers. Research in the area of mucoadhesive drug delivery systems has shed light on other properties of some of the mucoadhesive polymers. One important class of mucoadhesive polymers, poly(acrylic acid) derivatives, has been identified as potent inhibitors of proteolytic enzymes [72-74]. The interaction between various types of mucoadhesive polymers and epithelial cells has a direct influence on the permeability of mucosal epithelia by means of changing the gating properties of the tight jrmctions. More than being only adhesives, some mucoadhesive polymers can therefore be considered as a novel class of multifunctional macromolecules with a number of desirable properties for their use as delivery adjuvants [72,75]. 

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