d- and l-Polyconidine

Toy, Madeline S.; Price, Charles C.

doi:10.1021/ja01495a055

Cited by 41 publications

(14 citation statements)

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“…The synthesis and homopolymerization of this monomer was first published in I960. Several authors studied the mechanism (Equation I6a,b) and kinetics of the polymerization (84)(85)(86).…”

Section: Linear Crystalline Polvflthvteniminamentioning

confidence: 99%

Synthetic Methods for Water-Soluble Monomers and Polymers

Butler

Zhang

1991

ACS Symposium Series

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This review is based on a lecture that has been presented over the past several years by one of us (GBB) in connection with certain well-established short courses. Although the major water-soluble non-polyelectrolytes are covered briefly in this review, the major emphasis is placed on well-studied and either commercially available polyelectrolyte monomers or such monomers which have the potential for commercial development.The latter judgment is based on availability of raw materials, monomer and polymer yields, and/or quality of derivable polymers or copolymer. In many cases, only the monomers are emphasized, since methods for their polymerization generally parallel each other, all being predominantly initiated and polymerized via free radical mechanisms. No distinction is generally made among the several polymerization techniques such as aqueous or other solution processes, suspension or emulsion processes. In many cases all types have been studied. In most of the others, success in the application of the several techniques to the polymerization process can reasonably be predicted.Organic compounds having hydrophilic groups are soluble in water provided the hydrophobic-hydrophilic balance is favorable. Alcohols of low molecular weight are soluble in water; however, those of higher molecular weight are no longer soluble. The same principles apply to polymers. Table I includes the more common functional groups which impart water-solubility to organic compounds as well as to polymers. Non-polyelectrolytesAside from the naturally occurring water-soluble polysaccharides or their synthetically modified derivatives, the major contributors to the non-polyelectrolyte group of water-soluble polymers are: poly(acrylamide), poly(acrylic) or (methacrylic acids), poly(ethylene oxides), poly(methyl vinyl ether) and poly(vinyl alcohols). Polyacrylamide (PAM). Acrylamide polymerizes easily in aqueous solution inpresence of a wide variety of free-radical initiators (J_). Many added salts affect polymerization rate and molecular weight. Often, commercially produced poly(acrylamides) may contain a fraction that appears to be insoluble in water, a property which presents a problem for many uses. Much attention

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“…The synthesis and homopolymerization of this monomer was first published in I960. Several authors studied the mechanism (Equation I6a,b) and kinetics of the polymerization (84)(85)(86).…”

Section: Linear Crystalline Polvflthvteniminamentioning

confidence: 99%

Synthetic Methods for Water-Soluble Monomers and Polymers

Butler

Zhang

1991

ACS Symposium Series

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“…Several issues were foreseen in the acylation step, which were addressed before establishing the methods amenable to large scale operation. Chiral 2-hydroxyethylpiperidine ( 12) was obtained by a slight modification of the procedure of Toy . First, l -10-camphorsulfonate of 12 ( l − l ‘ salt) was prepared by optical resolution of racemic compound in ethanol, followed by recrystallization from ethanol.…”

Section: Resultsmentioning

confidence: 99%

Process Development of a Novel Non-Xanthine Adenosine A₁ Receptor Antagonist

Zanka

Uematsu

Morinaga

et al. 1999

Org. Process Res. Dev.

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(+)−(R)-1-[(E)-3-(2-phenylpyrazolo[1,5-a]pyridin-3-yl)acryloyl]-2-piperidine ethanol (FK453) is a novel, potent adenosine A1 receptor antagonist for the regulation of renal function. The development of a reliable process suitable for large scale manufacture is described. A Horner−Emmons reaction and a 1,3-dipolar cycloaddition were successfully scaled up to afford ethyl (E)-3-(2-phenylpyrazolo[1,5-a]pyridin-3-yl)acryloylate, with excellent regioselectivity and stereoselectivity. Process improvements and optimization of each step permitted elimination of column chromatography, resulting in a straightforward, practical synthesis of FK453.

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“…4 The synthesized esters were triply distilled. The purity of compounds 5--10 was confirmed by elemental analysis (Table 1).…”

Section: Methodsmentioning

confidence: 99%

The influence of the structure of tetracoordinate phosphorus acid esters on the catalytic effect of the sodium dodecyl sulfate-hexanol-water ternary reverse micellar system

et al. 2000

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The catalytic effect of the sodium dodecyl sulfate--hexanol--water ternary, reverse micellar system in the alkaline hydrolysis of O-alkyl O'-aryl chloromethylphosphonates as a function of the substrate structure was studied. The micellar effect is mainly determined by a change in the electronic properties of the substituents, while the hydrophobicity plays a secondary role. The kinetic data were examined in the framework of the pseudo-phase model of micellar catalysis. The rate constants of the reaction in the surface layer and the partition constants of the reactants were calculated.Key words: reverse micelles, pseudo-phases, surface layer, kinetics, hydrolysis, phosphonates.Reverse micelles are widely known as biomimetic structures that work according to the "guest--host" principle. ! The main qualitative regularities of catalysis of chemical reactions in these systems are poorly studied and only a few quantitative studies were performed. We have previously z,3 shown that in the reverse micellar system sodium bis(2-ethylhexyl) sulfosuccinate (AOT)--decane--water the alkaline hydrolysis of phosphonates proceeds more slowly than in water, and in the system sodium dodecyl sulfate (SDS)--hexanol--water the reaction is accelerated. To reveal the main reasons for catalysis of reactions and to solve the problem of substrate specificity in these organized media, the range of substrates under study should be enlarged. With this purpose, we studied the kinetics of the hydrolysis of O-alkyl O'-aryl chloromethylphosphonates (!--10) (Scheme I) at different ratios Z = [hexanoll/[SDS] and W = [H20]/ISDS ] and examined the kinetic data in the framework of the pseudo-phase model of micellar catalysis. ExperimentalCompounds 1--10 were prepared by a known procedure. 4 The synthesized esters were triply distilled. The purity of compounds 5--10 was confirmed by elemental analysis (Table 1). Phosphonates 1--4 have been synthesized by us previously, s SDS (high-purity grade) was doubly recrystallized From ethanol. Reverse micellar systems were prepared by the mixing of three components according to the phase diagram 6,7 followed by shaking to the formation of a transparent solution. The molar ratios W= [H2OI/ISDS ] and Z= [hexanoll/ [SDS] were varied in the intervals of 9.8--37 and 5--49, respectively. The reaction kinetics was studied spectrophotometrically on a Specord M-400 XRO/P u + H20 X = NO 2, R = Et (1), Bu n (2), n-CsH13 (3), n-Cell17 (4); R = Et, X = Br (5), H (6), Et (7), Bu n (8), n-CsH~7 (9), iso-C12H25 (|0)instrument by the change in the optical density of the anion of the leaving group. The initial concentration of the substrate was 5-10 -5 mol L -l, and the concentration of the nucleophile much exceeded that of the substrate. The observed rate constants (kobs) were calculated using the weighted least-squares method from the dependence ln(D,~-D) = -kobs t + const, where D and D= were the optical densities of the solution at the moment t and at the end of the reaction. The kinetic data were examined according to the ps...

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d- and l-Polyconidine

Cited by 41 publications

References 0 publications

Synthetic Methods for Water-Soluble Monomers and Polymers

Synthetic Methods for Water-Soluble Monomers and Polymers

Process Development of a Novel Non-Xanthine Adenosine A₁ Receptor Antagonist

The influence of the structure of tetracoordinate phosphorus acid esters on the catalytic effect of the sodium dodecyl sulfate-hexanol-water ternary reverse micellar system

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d- and l-Polyconidine

Cited by 41 publications

References 0 publications

Synthetic Methods for Water-Soluble Monomers and Polymers

Synthetic Methods for Water-Soluble Monomers and Polymers

Process Development of a Novel Non-Xanthine Adenosine A1 Receptor Antagonist

The influence of the structure of tetracoordinate phosphorus acid esters on the catalytic effect of the sodium dodecyl sulfate-hexanol-water ternary reverse micellar system

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Process Development of a Novel Non-Xanthine Adenosine A₁ Receptor Antagonist