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Without using any catalysts, a variety of epoxides undergo ring-opening by aromatic amines to afford the corresponding 1,2-amino alcohols in high to excellent yields with good regioselectivity in the presence of water as solvent and under solvent-free conditions  

Regioselective epoxides ring opening with aromatic amines using boric acid and glycerol in water as a green media have been investigated. Corresponding β-amino alcohols were obtained with excellent yields and considerable regioselectivity. High yields of the products and mild reaction conditions using green catalyst and water as a green solvent are some advantages of this procedure  

A simple and efficient synthesis of diol diesters, protected chlorohydrins, chlorohydrins and β-hydroxy azides with acetyl or benzoyl, TMSN3 and TMSCl groups has been achieved by ring opening of epoxides with acetic anhydride, acetyl chloride or benzoyl chloride and TMSN3 using catalytic amount of lithium perchlorate under solvent-free conditions. All reactions proceeded in short times and afforded the corresponding products in good to excellent yields under mild reaction conditions. LiClO4 shows enhanced reactivity for the ring opening of epoxides under solvent-free conditions, therefore, reducing the reaction times dramatically and improved the yields and amount of catalyst. © 2007... 

Heteropoly acid was found to be an effective and efficient catalyst for the ring opening reaction of epoxides with various aromatic amines to produce the corresponding β-amino alcohols in moderate to excellent yields in water. This method provides a new and efficient protocol in terms of mild reaction conditions, clean reaction profiles, small quantity of catalyst, and simple work-up procedure. © 2006  

Efficient synthesis of protected and unprotected chlorohydrins has been achieved by ring opening of epoxides with acetyl/benzoyl chloride and TMSCl using a catalytic amount of ZnO as a reusable catalyst. The applicability of ZnO is further extended by performing the cleavage of the natural product 5,6-epoxysitosterol with acetyl chloride. © 2009 Wiley Periodicals, Inc  

An environmentally benign, aqueous synthesis of 1,2-azidoalcohols via regioselective ring opening of their epoxides using magnetic imidazolium based dicationic room temperature ionic liquid, [pbmim](FeCl4)2, as an efficient magnetic phase transfer catalyst in water has been described. The present approach offers the advantages of clean reaction, simple methodology, short reaction time, high yield, easy purification and reusable catalyst  

Thermally oxidized nanodiamond (OND), amine-functionalized ND (AND) and untreated ND (UND) were added to epoxy/TETA at 1 wt % loading. The ND enhanced the dynamic storage modulus of epoxy while decreasing the glass transition temperature because of the increment of free volume in the vicinity of the ND surfaces. The ND induced an acceleration effect on the curing reaction which could be due to functional groups of the ND and lack of any steric hindrance on molecules by the ND particles themselves. The Vyazovkin model-free isoconversional method indicated that all NDs decreased the activation energy; among them, AND showed the lowest value because of the significant promotion of the epoxide... 

Three versions of zirconium-based metal organic frameworks, NH2-UiO-66, GMA-UiO-66, and EDA-UiO-66, were synthesized and employed as adsorbent for CO2/CH4 separation. GMA-UiO-66 was synthesized via a ring opening reaction between the amine species in the framework and epoxy groups in glycidyl methacrylate (GMA), while the green aza-Michael addition reaction was used for the first time to functionalize GMA-UiO-66 with ethylenediamine (EDA). The products were characterized by BET, XRD, TGA, FESEM, ICP-OES, 1H NMR, mass spectroscopy, and FTIR-ATR methods to monitor their textural properties before and after functionalization. The results indicated that GMA was successfully grafted to the... 

The synthesis of nanocomposites via in situ grafting polymerization due to its ability to produce polymeric materials with promising microscopic and macroscopic characteristics is becoming very attractive. In this paper, different poly(L-Lactide)-block-poly(ε-caprolactone) (PLLA-b-PCL) copolymers were in situ synthesized in the presence of modified titanium dioxide (TiO2) nanoparticles (mTNP) as the initiator and stannous octoate as the catalyst. The surface of TiO2 was modified by grafting aminopropyl trimethoxy silane to improve initiator efficiency. Copolymers with 90/10, 70/30, and 50/50 mass ratio of L-lactide/ ε-caprolactone and 5 wt% of mTNP (proportional to ε-caprolactone) were... 

In the present work, a simple, green, rapid, and catalyst-free procedure for the synthesis of benzamide derivatives by ring opening of azlactones with diamines such as ethylene diamine and 1,3-propylenediamine is described. The present method offers several advantages such as short reaction times, easy work-up, and mild reaction conditions in the absence of catalyst and any toxic solvent and material. In addition, the structure obtained by X-ray crystallography was compared with the theoretical results obtained by density functional theory using the B3LYP functional and cc-pVDZ basis sets  

Polycaprolactone-polylactide block copolymers (PCL-block-PLA) were grafted onto filled multi-wall carbon nanotubes (MWCNT) successfully. In this synthesis, MWCNTs were opened and functionalized, and then they were filled by silver nanoparticles. The filled MWCNT were used as macroinitiator for ring opening polymerization of ε-caprolactone and L-lactide. Then the end hydroxyl functional groups of MWCNT-graft-PCL or MWCNT-graft-PLA were used as initiator for ring opening polymerization of lactide and ε-caprolactone and MWCNT-graft-PCL-block-PLA or MWCNT-graft-PLA-block-PCL were obtained, respectively. Length of grafted copolymer chains onto the MWCNT was controlled using CNT/monomer ratio.... 

In this study, injectable PEG-based hydrogels containing Laponite particles with mechanical and structural properties close to the natural articular cartilage are introduced. The nanocomposites are fabricated by imide ring opening reactions utilizing synthesized copolymers containing PEG blocks and nanoclay through a two-step thermal poly-(amic acid) process. Butane diamine is used as nucleophilic reagent and hydrogels with interconnected pores with sizes in the range of 100–250 µm are prepared. Improved viscoelastic properties compared with the conventional PEG hydrogels are shown. Evaluation of cell viability utilizing human mesenchymal stem cells determines cytocompatibility of the... 

New biocompatible and water soluble hybrid materials containing multi-wall carbon nanotubes (MWCNTs) as core and hyperbranched polyglycerol (PG) as shell were synthesized successfully. In this work, pristine MWCNTs were opened and functionalized through treatment with acid and polyglycerol was covalently grafted onto their surface by the "grafting from" approach based on in-situ ring-opening polymerization of glycidol. Some short-term In vitro cytotoxicity and hemocompatibility tests were conducted on HT1080 cell line (human Fibrosarcoma), because this epithelial cell line can be one of the first route of entry of the exogenous materials to the vascular system and therefore subsequent... 

Herein, we report the preparation of novel magnetic graphene oxide (GO) grafted with brush polymer via surface-initiated reversible addition-fragmentation chain transfer (SI-RAFT) polymerization and its application as a nanocarrier for magnetic- and pH-triggered delivery of doxorubicin anticancer drug. The RAFT agent, DDMAT, was firstly attached to the surface of magnetic GO nanosheets. The DDMAT-functionalized magnetic GO nanosheets were then used to polymerize glycidyl methacrylate (GMA) using an SI-RAFT method. Afterwards, the epoxy rings of the PGMA chains were opened with hydrazine (N2H4) moieties. The resulting nanocomposite was used as a drug carrier for doxorubicin (DOX) as an... 

Herein, we report the preparation of novel magnetic graphene oxide (GO) grafted with brush polymer via surface-initiated reversible addition-fragmentation chain transfer (SI-RAFT) polymerization and its application as a nanocarrier for magnetic- and pH-triggered delivery of doxorubicin anticancer drug. The RAFT agent, DDMAT, was firstly attached to the surface of magnetic GO nanosheets. The DDMAT-functionalized magnetic GO nanosheets were then used to polymerize glycidyl methacrylate (GMA) using an SI-RAFT method. Afterwards, the epoxy rings of the PGMA chains were opened with hydrazine (N2H4) moieties. The resulting nanocomposite was used as a drug carrier for doxorubicin (DOX) as an... 

Lithium perchlorate has been found to be an inexpensive and efficient catalyst for the ring opening of epoxides by indole and N-methylindole, which provides an environmentally friendly method for the synthesis of substituted indoles. A complete regioselectivity in favor of nucleophilic attack at the benzylic carbon atom of aromatic epoxides, such as styrene oxide, is observed. However, aliphatic unsymmetrical alkene oxides undergo selective nucleophilic attack at the sterically less-hindered carbon atom. This catalyst offers several advantages, such as short reaction time, high yields, lower catalytic loading, simple experimental procedure, and easy isolation of the products, under... 

Lithium perchlorate catalyzed the ring opening of epoxides with amines to provide the corresponding β-aminoalcohols in excellent yields with high regioselectivity. The reaction proceeds rapidly under mild and neutral conditions and worked well with primary, secondary, aliphatic, aromatic, and hindered amines in short times at room temperature, in the absence of solvent. © 2005 NRC Canada