20 research outputs found
The preparation of graft copolymers of cellulose and cellulose derivatives using ATRP under homogeneous reaction conditions
In this comprehensive review, we report on the preparation of graft-copolymers of cellulose and cellulose derivatives using atom transfer radical polymerization (ATRP) under homogeneous conditions. The review is divided into four sections according to the cellulosic material that is graft-copolymerised; (i) cellulose, (ii) ethyl cellulose, (iii) hydroxypropyl cellulose and (iv) other cellulose derivatives. In each section, the grafted synthetic polymers are described as well as the methods used for ATRP macro-initiator formation and graft-copolymerisation. The physical properties of the graft-copolymers including their self-assembly in solution into nanostructures and their stimuli responsive behaviour are described. Potential applications of the self-assembled graft copolymers in areas such as nanocontainers for drug delivery are outline
The preparation of graft copolymers of cellulose and cellulose derivatives using ATRP under homogeneous reaction conditions
<b>A solvent free and selective method for preparation of triphenylmethyl ethers of alcohols and nucleosides</b>
A very simple and efficient method is described for protection of alcohols and nucleosides with trityl(triphenylmethyl), mono and dimethoxytrityl chlorides in the presence of triethylamine under microwave irradiation. High selectivity was observed for tritylation of 5'-OH function of nucleosides
An efficient and highly selective ortho-tert-butylation of p-cresol with methyl tert-butyl ether catalyzed by sulfonated ionic liquids
A novel series of sulfonic acid-functionalized ionic liquids (SFILs) was
found to act as efficient catalysts for ortho-tert-butylation of p-cresol
with methyl tert-butyl ether (MTBE) as the tert-butylating agent without an
added solvent. The mono o-tert-butylated product was obtained in up to 80.4%
isolated yield and 95.2% selectivity under such green conditions. No
O-tert-butylated byproducts were formed
Application of highly sulfonated single-walled carbon nanotubes: An efficient heterogeneous catalyst for the one-pot synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes under solvent-free conditions
A New Neural Network−Group Contribution Method for Estimation of Flash Point Temperature of Pure Components
Application of highly sulfonated single-walled carbon nanotubes: An efficient heterogeneous catalyst for the one-pot synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes under solvent-free conditions
Solitary Crossed Renal Ectopia: Concurrence of Posterior Urethral Valve and Hypospadias
Solitary crossed
renal ectopia (SCRE) represents an exceedingly
rare congenital disorder. Although skeletal and
genitourinary abnormalities most commonly
accompany this condition, vesicoureteral reflux
(VUR) has been described in only a few cases.
Here, we present two unique cases of SCRE
complicated by high-grade VUR concomitant with
posterior urethral valve in one case and
hypospadias in the other one. We also provide a brief
review of the literature on this
subject
Cooperative Activation in the Synthesis of Flavanone Antioxidants Using a Simple and Highly Efficient Magnetically Recoverable Nano-Cu-CoFe<sub>2</sub>O<sub>4</sub> Catalyst
<p>Double mixed Cu<sub>0.5</sub>Co<sub>0.5</sub>Fe<sub>2</sub>O<sub>4</sub> ferrite nanoparticles were found as a highly efficient and magnetically separable nanocatalyst for the synthesis of varied flavanone antioxidants. A wide range of flavanone derivatives were prepared with excellent isolated yields within the short reaction times. The catalyst could be separated using a simple magnetic extraction and reused 6 times with no remarkable loss of activity. The high activity of the prepared catalyst was attributed to the cooperative activation of the carbonyl group by both copper and cobalt via a synergistic catalytic effect that facilitates the Micheal addition of the hydroxyl group to the α,β-unsaturated ketone.</p
Sulfonated Reduced Graphene Oxide (RGO-SO<sub>3</sub>H): As an Efficient Nanocatalyst for One-Pot Synthesis of 2-Amino-3-cyano-7-hydroxy-<i>4H</i>-chromenes Derivatives in Water
<p>Sulfonated reduced graphene oxide (RGO-SO<sub>3</sub>H) was found to be an efficient catalyst for one-pot synthesis of a class of 2-amino-3-cyano-7-hydroxy-4H-chromenes derivatives using multicomponent reaction (MCR) of phenols, aldehydes and malononitrile under mild and green conditions. The reaction was performed in water as a green solvent and range of 2-amino-3-cyano-7-hydroxy-4H-chromenes were obtained in good to excellent yields. The RGO-SO<sub>3</sub>H was reusable at least 5 times without significant decrease in its catalytic activity.</p