scholarly journals Systematic synthetic study of four diastereomerically distinct limonene-1,2-diols and their corresponding cyclic carbonates

2019 ◽  
Vol 15 ◽  
pp. 130-136 ◽  
Author(s):  
Hiroshi Morikawa ◽  
Jun-ichi Yamaguchi ◽  
Shun-ichi Sugimura ◽  
Masato Minamoto ◽  
Yuuta Gorou ◽  
...  
Keyword(s):  
Cyclic Carbonate ◽  
Cyclic Carbonates ◽  
Stereochemical Configuration ◽  
Nmr Data ◽  
Limonene Oxide ◽  
High Yields ◽  
High Stereoselectivity

In order to produce versatile and potentially functional terpene-based compounds, a (R)-limonene-derived diol and its corresponding five-membered cyclic carbonate were prepared. The diol (cyclic carbonate) comprises four diastereomers based on the stereochemical configuration of the diol (and cyclic carbonate) moiety. By choosing the appropriate starting compounds (trans- and cis-limonene oxide) and conditions, the desired diastereomers were synthesised in moderate to high yields with, in most cases, high stereoselectivity. Comparison of the NMR data of the obtained diols and carbonates revealed that the four different diastereomers of each compound could be distinguished by reference to their characteristic signals.

scholarly journals Cycloaddition Reaction of Carbon Dioxide to Epoxides Catalyzed by Polymer-Supported Quaternary Phosphonium Salts

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Yubing Xiong ◽  
Feng Bai ◽  
Zipeng Cui ◽  
Na Guo ◽  
Rongmin Wang
Keyword(s):  
Carbon Dioxide ◽  
Low Cost ◽  
Cycloaddition Reaction ◽  
Coupling Reaction ◽  
Catalytic Performance ◽  
Cyclic Carbonate ◽  
Cyclic Carbonates ◽  
Phosphonium Salts ◽  
Polymer Supported ◽  
High Yields

Polymer-supported quaternary phosphonium salt (PS-QPS) was explored as effective catalyst for the coupling reaction of carbon dioxide with epoxides. The results indicated that cyclic carbonates with high yields (98.6%) and excellent selectivity (100%) could be prepared at the conditions of 5 MPa CO2, 150°C, and 6 h without the addition of organic solvents or cocatalysts. The effects of various reaction conditions on the catalytic performance were investigated in detail. The catalyst is applicable to a variety of epoxides, producing the corresponding cyclic carbonates in good yields. Furthermore, the catalyst could be recovered easily and reused for five times without loss of catalytic activity obviously. A proposed mechanism for synthesis of cyclic carbonate in the presence of PS-QPS was discussed. The catalyst was characterized by thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and Fourier transform infrared (FT-IR) spectrum. It is believed that PS-QPS is of great potential for CO2fixation applications due to its unusual advantages, such as easy preparation, high activity and selectivity, stability, low cost, and reusability.

scholarly journals Towards Automated Monomer Synthesis: A Streamlined Approach for the Synthesis of Cyclic Carbonates

2020 ◽  
Author(s):  
Eddy Wei Ping Tan ◽  
James L. Hedrick ◽  
Pedro Luis Arrechea ◽  
Tim Erdmann ◽  
Vivien Kiyek ◽  
...  
Keyword(s):  
Functional Groups ◽  
Ring Opening ◽  
Ring Opening Polymerization ◽  
Cyclic Carbonate ◽  
Cyclic Carbonates ◽  
Chromatographic Purification ◽  
Materials Synthesis ◽  
Experimental Systems ◽  
Broad Array ◽  
High Yields

Accessing cyclic carbonate monomers on large scales is critical for development of any new carbonate-based material platform. This is particularly important in the context of using automated experimental systems for materials synthesis, which can often require large inputs of starting materials. However, the synthesis of carbonate monomers can be a challenging and tedious endeavor, requiring multiple synthetic steps and purifications. To address this, we report a drastically improved and scalable process for the synthesis of carbonate monomers via a two-step route that avoids the use of hazardous phosgene or chloroformate reagents. The cyclic carbonate monomers can be obtained in high yields and with minimal need for chromatographic purification. This process enables rapid access to a broad array of functional groups on the carbonate monomer and monomers generated from procedure can readily be polymerized via ring-opening polymerization.<br>

scholarly journals Towards Automated Monomer Synthesis: A Streamlined Approach for the Synthesis of Cyclic Carbonates

2020 ◽  
Author(s):  
Eddy Wei Ping Tan ◽  
James L. Hedrick ◽  
Pedro Luis Arrechea ◽  
Tim Erdmann ◽  
Vivien Kiyek ◽  
...  
Keyword(s):  
Functional Groups ◽  
Ring Opening ◽  
Ring Opening Polymerization ◽  
Cyclic Carbonate ◽  
Cyclic Carbonates ◽  
Chromatographic Purification ◽  
Materials Synthesis ◽  
Experimental Systems ◽  
Broad Array ◽  
High Yields

Accessing cyclic carbonate monomers on large scales is critical for development of any new carbonate-based material platform. This is particularly important in the context of using automated experimental systems for materials synthesis, which can often require large inputs of starting materials. However, the synthesis of carbonate monomers can be a challenging and tedious endeavor, requiring multiple synthetic steps and purifications. To address this, we report a drastically improved and scalable process for the synthesis of carbonate monomers via a two-step route that avoids the use of hazardous phosgene or chloroformate reagents. The cyclic carbonate monomers can be obtained in high yields and with minimal need for chromatographic purification. This process enables rapid access to a broad array of functional groups on the carbonate monomer and monomers generated from procedure can readily be polymerized via ring-opening polymerization.<br>

scholarly journals Highly Efficient MOF Catalyst Systems for CO2 Conversion to Bis-Cyclic Carbonates as Building Blocks for NIPHUs (Non-Isocyanate Polyhydroxyurethanes) Synthesis

Catalysts ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 628
Author(s):  
Adolfo Benedito ◽  
Eider Acarreta ◽  
Enrique Giménez
Keyword(s):  
Molar Mass ◽  
Cycloaddition Reaction ◽  
Building Blocks ◽  
Catalyst System ◽  
Cyclic Carbonate ◽  
Ammonium Bromide ◽  
Cyclic Carbonates ◽  
High Molar Mass ◽  
Highly Efficient ◽  
Free Process

The present paper describes a greener sustainable route toward the synthesis of NIPHUs. We report a highly efficient solvent-free process to produce [4,4′-bi(1,3-dioxolane)]-2,2′-dione (BDC), involving CO2, as renewable feedstock, and bis-epoxide (1,3-butadiendiepoxide) using only metal–organic frameworks (MOFs) as catalysts and cetyltrimethyl-ammonium bromide (CTAB) as a co-catalyst. This synthetic procedure is evaluated in the context of reducing global emissions of waste CO2 and converting CO2 into useful chemical feedstocks. The reaction was carried out in a pressurized reactor at pressures of 30 bars and controlled temperatures of around 120–130 °C. This study examines how reaction parameters such as catalyst used, temperature, or reaction time can influence the molar mass, yield, or reactivity of BDC. High BDC reactivity is essential for producing high molar mass linear non-isocyanate polyhydroxyurethane (NIPHU) via melt-phase polyaddition with aliphatic diamines. The optimized Al-OH-fumarate catalyst system described in this paper exhibited a 78% GC-MS conversion for the desired cyclic carbonates, in the absence of a solvent and a 50 wt % chemically fixed CO2. The cycloaddition reaction could also be carried out in the absence of CTAB, although lower cyclic carbonate yields were observed.

scholarly journals Spin-labeling of Dexamethasone: Radical Stability vs. Temporal Resolution of EPR-Spectroscopy on Biological Samples

2018 ◽  
Vol 232 (5-6) ◽  
pp. 883-891 ◽  
Author(s):  
Karolina A. Walker ◽  
Michael L. Unbehauen ◽  
Silke B. Lohan ◽  
Siavash Saeidpour ◽  
Martina C. Meinke ◽  
...  
Keyword(s):  
Detection Limit ◽  
Hydroxy Group ◽  
Epr Spectroscopy ◽  
Biological Samples ◽  
Spin Labeling ◽  
Hacat Cells ◽  
Nmr Data ◽  
Primary Hydroxy Group ◽  
High Yields ◽  
Stability Measurements

AbstractSpin-labeling active compounds is a convenient way to prepare them for EPR spectroscopy with minimal alteration of the target molecule. In this study we present the labeling reaction of dexamethasone (Dx) with either TEMPO (2,2,6,6-tetramethyl-1-piperidinyloxy) or PCA (3-(carboxy)-2,2,5,5-tetramethyl-1-pyrrolidinyloxy) with high yields. According to NMR data, both labels are attached at the primary hydroxy group of the steroid. In subsequent spin-stability measurements both compounds were applied onto HaCaT cells. When the signal of Dx-TEMPO decreased below the detection limit within 3 h, the signal of Dx-PCA remained stable for the same period of time.

Bimetallic scorpionate-based helical organoaluminum complexes for efficient carbon dioxide fixation into a variety of cyclic carbonates

2020 ◽  
Vol 10 (10) ◽  
pp. 3265-3278 ◽  
Author(s):  
Marta Navarro ◽  
Luis F. Sánchez-Barba ◽  
Andrés Garcés ◽  
Juan Fernández-Baeza ◽  
Israel Fernández ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Cyclic Carbonate ◽  
Carbon Dioxide Fixation ◽  
Cyclic Carbonates ◽  
Carbonate Formation ◽  
Aluminum Complexes

The binuclear aluminum complexes [AlR2(κ2-NN′;κ2-NN′)AlR2] with TBAB/PPNCl behave as excellent systems for cyclic carbonate formation from CO2 with challenging epoxides.

Two Diastereomers of d-Limonene-Derived Cyclic Carbonates from d-Limonene Oxide and Carbon Dioxide with a Tetrabutylammonium Chloride Catalyst

2018 ◽  
Vol 91 (1) ◽  
pp. 92-94 ◽  
Author(s):  
Hiroshi Morikawa ◽  
Masato Minamoto ◽  
Yuuta Gorou ◽  
Jun-ichi Yamaguchi ◽  
Hisatoyo Morinaga ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Cyclic Carbonates ◽  
Chloride Catalyst ◽  
Limonene Oxide ◽  
Tetrabutylammonium Chloride

Cyclic carbonates as monomers for phosgene- and isocyanate-free polyurethanes and polycarbonates

2011 ◽  
Vol 84 (3) ◽  
pp. 637-661 ◽  
Author(s):  
Sang-Hyun Pyo ◽  
Per Persson ◽  
M. Amin Mollaahmad ◽  
Kent Sörensen ◽  
Stefan Lundmark ◽  
...  
Keyword(s):  
Ring Opening ◽  
High Performance ◽  
Optical Devices ◽  
Cyclic Carbonate ◽  
Cyclic Carbonates ◽  
Catalyst Metal ◽  
Recent Developments ◽  
Metallic Catalyst ◽  
Low Toxicity ◽  
Safety Procedures

Polyurethanes and polycarbonates are widely used in a variety of applications including engineering, optical devices, and high-performance adhesives and coatings, etc., and are expected to find use also in the biomedical field owing to their biocompatibility and low toxicity. However, these polymers are currently produced using hazardous phosgene and isocyanates, which are derived from the reaction between an amine and phosgene. Extensive safety procedures are required to prevent exposure to phosgene and isocyanate because of its high toxicity. Therefore, the demand for the production of isocyanate-free polymers has now emerged. Among the alternative greener routes that have been proposed, a popular way is the ring-opening polymerization (ROP) of cyclic carbonate in bulk or solution, usually using metallic catalyst, metal-free initiator, or biocatalyst. This review presents the recent developments in the preparation and application of cyclic carbonates as monomers for ROP, with emphasis on phosgene- and isocyanate-free polymerization to produce aliphatic polycarbonates and polyurethanes and their copolymers.

scholarly journals Poly(hydroxyurethane): catalytic applicability for the cyclic carbonate synthesis from epoxides and CO2

2020 ◽  
Vol 56 (73) ◽  
pp. 10678-10681
Author(s):  
Suguru Motokucho ◽  
Hiroshi Morikawa
Keyword(s):  
High Selectivity ◽  
Cyclic Carbonate ◽  
Chemical Fixation ◽  
Cyclic Carbonates ◽  
Synthetic Methodology

We have developed a synthetic methodology using poly(hydroxyurethane) as an organocatalyst for the chemical fixation of CO2 into epoxides, leading to the formation of five-membered cyclic carbonates with remarkably high selectivity and yields.

Lewis Acid-Catalyzed Rearrangement of Fluoroalkylated Propargylic Alcohols: An Alternative Approach to β-Fluoroalkyl-α,β-enones

Synlett ◽  
2019 ◽  
Vol 30 (03) ◽  
pp. 356-360 ◽  
Author(s):  
Manickavasakam Ramasamy ◽  
Hui-Chang Lin ◽  
Sheng-Chu Kuo ◽  
Min-Tsang Hsieh
Keyword(s):  
Lewis Acid ◽  
Propargylic Alcohols ◽  
Alternative Approach ◽  
Acid Catalyzed ◽  
High Yields ◽  
High Stereoselectivity

A practical Lewis acid-catalyzed Meyer–Schuster rearrangement of fluoroalkylated propargylic alcohols, leading to a series of β-fluoroalkyl-α,β-enones, is developed. The methodology reported herein features moderate to high yields and high stereoselectivity in the synthesis of β-alkyl-β-fluoroalkyl-α,β-enones.

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