Pentaerythritol Derivatives Research Articles

Host-Guest Complexations Between Pillar[6]arenes and Neutral Pentaerythritol Derivatives.

It is demonstrated that three kinds of neutral pentaerythritol derivatives possess promising host-guest complexations with pillar[6]arenes both in solution and in the solid state. The inclusion structures were characterized by NMR spectroscopy and X-ray crystallography. The complexation properties in different solvents were also investigated.

Flame-retardant effect of cross-linked phosphazene derivatives and pentaerythritol derivatives on polypropylene

A phosphazene-based flame retardant (PBFA) was synthesized by hexachlorocyclotriphosphazene and N-aminoethylpiperazine. To improve the flame retardancy of polypropylene (PP), PBFA and pentaerythritol derivatives (PEPA) were mechanically mixed to form a water resistance intumescent flame retardant (IFR). The flammability and thermal properties of the PP composites were analyzed by vertical burning test (UL-94), limit oxygen index, thermogravimetric analysis (TGA) and cone calorimeter test (CCT). The results indicate that there was a synergistic effect between PBFA and PEPA at a suitable mass ratio. When the mass ratio of PBFA/PEPA was 2:1, the PP composites can successfully achieve UL-94 V 0 rating. Compared with pure PP, the peak heat release rate and the total heat release were decreased by 75.40 and 15.38%, respectively; moreover, the total smoke production decreased by 22.11% during 0–465 s. The residual char after CCT was characterized by Fourier transform infrared spectrometer (FTIR). A strong pyrophosphate absorption peak was found in FTIR, indicating that the IFR mainly played a flame-retardant mechanism in the condensed phase.

Catalytic Transesterification Routes to Novel Vinyl Glycolate Derivatives of Polyhydric Alcohols

Methyl vinyl glycolate (methyl 2-hydroxybut-3-enoate, MVG) has recently become obtainable from Sn catalysed cascade reactions of mono- and disaccharides. The chemical structure of MVG present several options for chemical transformations and has great potential as a renewable platform chemical for industrial added-value compounds within e.g. polymer chemistry. Herein, we report a catalytic benign transesterification method for the synthesis of MVG ester derivatives of trimethylolpropane (TMP) and pentaerythritol (PE). The secondary alcohol group of MVG greatly complicates the reaction and requires a highly selective catalyst to direct the reaction towards high conversion while avoiding polymerization. Thus, a range of different catalytic systems, e.g. Candida Antarctica Lipase B (CALB), Bronsted bases/acids, salicylic aldehyde as well as Lewis acids were evaluated for the reaction. Despite the challenges this leads to unique derivatives of TMP and PE with an additional chemical handle compared to classic derivatives like the methacrylate and mercaptopropionate.

Effect of oligo(spiroorthocarbonate)s on the volume shrinkage of epoxides during crosslinking by sulfonium salt‐initiated cationic polymerization of epoxides

ABSTRACTOligo(spiroorthocarbonate)s 1, which were synthesized by the polycondensation of pentaerythritol derivatives with tetraethylorthocarbonate, were employed as comonomers in the cationic polymerization of epoxide initiated by sulfonium salt. In the copolymerization, the spiroorthocarbonate moiety of 1 underwent double ring‐opening reaction, leading to the efficient diminution of the volume shrinkage upon the copolymerization. Thermal properties of the resulting networked polymers were evaluated by TGA. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1564–1568

Efficient synthesis and properties of soluble aliphatic oligo(spiroorthocarbonate)s from pentaerythritol derivatives

ABSTRACTA series of soluble oligo(spiroorthocarbonate)s (OSOCs) were synthesized by polycondensation of tetraethylorthocarbonate with pentaerythritol derivatives. The pentaerythritol derivatives used herein were synthesized from pentaerythritol by attaching substituents on it to improve the solubility of themselves and the resulting OSOCs. The structures of the OSOCs were confirmed by NMR spectroscopy and MALDI‐TOF mass analysis. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 792–798

3,3-Bis(azidomethyl)oxetane (BAMO) Synthesis via Pentaerythritol Tosyl Derivates

3,3-Bis(azidomethyl)oxetane (BAMO) is the most widely known azido oxetane in terms of the number of its polymers and copolymers applied as energetic binders e.g. in rocket propellants and plastic formulations of explosive materials. However, this compound continues to be a rather expensive monomer today. The aim of this study was to find a suitable synthetic route to produce this monomer in a large scale and to optimize it. The chosen route of synthesis was based on the application of tosyl pentaerythritol derivatives as the starting material. The BAMO synthesis by this method involves three stages, namely: pentaerythritol tosylation, tritosylpentaerythritol cyclization to 3,3-bis(tosylmethyl)oxetane (BTMO), and substitution of the BTMO tosyl groups with azido groups. In this work all the stages of the synthesis were optimized. BAMO was obtained in an overall yield of 61 %. The structure of the obtained compounds was verified by two techniques, namely: 1HNMR and FT-IR.

Glycerol and esterified products of palmitic acid as a mixed plasticizer for thermoplastic tapioca starch

AbstractIn this work, a mixture of glycerol (Gly) and derivatives of pentaerythritol or α,α′‐diglycerol is used as a plasticizer for preparing a thermoplastic starch (TPS). A coplasticizer containing both hydroxyl group and a long aliphatic chain was synthesized by esterification reaction between pentaerythritol or α,α′‐diglycerol and palmitoyl chloride in two different molar ratios, that is, 1:1 (PT1 and DG1), 1:2 (PT2 and DG2). The esterification products were characterized using Fourier transform infrared spectroscopy, 1H, and 13C nuclear magnetic resonance spectroscopy. The starch and the mixed plasticizer were blended in an internal mixer. The morphology and miscibility of the blends were investigated by scanning electron microscope. The mechanical properties, moisture adsorption, and retrogradation phenomenon of the TPS specimens were studied. The results indicated that the TPS specimen containing a mixed plasticizer in a weight ratio of 80% Gly: 20% PT1 showed the highest values of Young's modulus and tensile strength, because this mixed plasticizer system could form stronger hydrogen bonds with starch molecules. Moreover, thermoplastic starch with higher content of pentaerythritol or α,α′‐diglycerol derivatives as a coplasticizer showed lower moisture adsorption, because its long aliphatic chain (hydrophobic part) of pentaerythritol derivatives may prevent starch molecules to reform hydrogen bonding and to recrystallize. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers

Synthesis and Evaluation of Nonsulfated and Sulfated Glycopolymers as L- and P-selectin Inhibitors

Selectins are carbohydrate-binding proteins and responsible for leukocyte extravasation in inflammation. Here we demonstrate the potential of synthetic glycocompounds as inhibitors for the selectin-ligand interaction. Pentaerythritol derivatives showed distinct selectin-binding properties with IC50 values up to 1.5 μM. Multivalent hyperbranched polyglycerol (hPG) derivatives did not lead to a substantial increase in inhibition, but a more than 1000-fold enhancement was realized when sulfated glyco-hPGs were tested. IC50 values in the high picomolar to low nanomolar range were obtained for selectin inhibition, which highlights the relevance of sulfate groups that seem to dominate the binding mode.

Host–guest complexes of cucurbit[8]uril with some pentaerythritol derivative guests

A series of first generation dendritic guests from pentaerythritol derivatives have been designed and synthesized. Investigation of the complex structures of cucurbit[8]uril (Q[8]) and the guests based on the 1H NMR technique have revealed that the host Q[8] selectively included different branch(es) of the first generation dendritic guests and formed inclusion complexes with different structural conformations. The experimental results obtained from electronic absorption spectroscopy showed that the 1 : 1 ratio of Q[8]-based host–guest inclusion complexes have moderate stability with an average formation constants of 104 L mol−1. The single crystal structures of some of the guests (g5 and g6) and Q[8]–guest complexes (Q[8]-g4 and Q[8]-g6) further confirm but in some cases contradict the research results of the 1H NMR technique and electronic absorption spectroscopy in aqueous solution.

Bioprinting vessel-like constructs using hyaluronan hydrogels crosslinked with tetrahedral polyethylene glycol tetracrylates

Bioprinting enables deposition of cells and biomaterials into spatial orientations and complexities that mirror physiologically relevant geometries. To facilitate the development of bioartificial vessel-like grafts, two four-armed polyethylene glycol (PEG) derivatives with different PEG chain lengths, TetraPEG8 and TetraPEG13, were synthesized from tetrahedral pentaerythritol derivatives. The TetraPEGs are unique multi-armed PEGs with a compact and symmetrical core. The TetraPEGs were converted to tetra-acrylate derivatives (TetraPAcs) which were used in turn to co-crosslink thiolated hyaluronic acid and gelatin derivatives into extrudable hydrogels for printing tissue constructs. First, the hydrogels produced by TetraPAc crosslinking showed significantly higher shear storage moduli when compared to PEG diacrylate (PEGDA)-crosslinked synthetic extracellular matrices (sECMs) of similar composition. These stiffer hydrogels have rheological properties more suited to bioprinting high-density cell suspensions. Second, TetraPAc-crosslinked sECMs were equivalent or superior to PEGDA-crosslinked gels in supporting cell growth and proliferation. Third, the TetraPac sECMs were employed in a proof-of-concept experiment by encapsulation of NIH 3T3 cells in sausage-like hydrogel macrofilaments. These macrofilaments were then printed into tubular tissue constructs by layer-by-layer deposition using the Fab@Home printing system. LIVE/DEAD viability/cytotoxicity-stained cross-sectional images showed the bioprinted cell structures to be viable in culture for up to 4 weeks with little evidence of cell death. Thus, biofabrication of cell suspensions in TetraPAc sECMs demonstrates the feasibility of building bioartificial blood vessel-like constructs for research and potentially clinical uses.

Synthesis and Liquid Crystalline Properties of Mono‐, Di‐ and Tri‐O‐alkyl Pentaerythritol Derivatives Bearing Tri‐, Di‐ or Monogalactosyl Heads: The Effects of Curvature of Molecular Packing on Mesophase Formation

Self-organisation and self-assembly are critical to the stability of synthetic and biological membranes. Of particular importance is consideration of the packing arrangements of the various molecular species. Both phospho- and glycolipids can pack in ways in which curvature can be introduced into self-organised or self-assembled systems. For instance, it is known that the degree of curvature can affect the structures of any condensed phases that are formed. In this article we report on a systematic study in which we have varied the shapes of glycolipids and examined the condensed phases that they form. In doing so, we have also unified the shape dependency of lyotropic liquid crystals with those of thermotropic liquid crystals. In order to undertake this systematic study a range of different pentaerythritol derivatives was synthesized, which covers combinations of one to three alkyl chains of different lengths (6,7,9,10,11,12,14,16 carbon atoms) and three to one galactosyl heads. Mono- and di-O-galactosyl derivatives were prepared directly by glycosylation of the corresponding alcohols using 2,3,4,6-tetra-O-benzoyl or acetyl-alpha-D-galactopyranosyl trichloroacetimidate or bromide as the donors; the tri-O-galactosyl derivatives were synthesized from O-alkyl-O-benzyl di-O-galactosyl pentaerythritol intermediates, followed by de-O-benzylation and glycosylation steps. All of the fully deprotected products were obtained by standard methods, and their self-organising and self-assembling properties examined.

The design and synthesis of highly branched and spherically symmetric fluorinated oils and amphiles

A new surfactant design principle, based on concepts borrowed from protein science, is proposed. Using this principle, a class of highly branched and spherically symmetric fluorinated oils and amphiles has been designed and synthesized, for potential applications in the construction of fluorocarbon nanoparticles. The Mitsunobu reaction was employed as the key step for introducing three perfluoro- tert-butoxyl groups into pentaerythritol derivatives with excellent yields and extremely simple isolation procedures. Due to the symmetric arrangement of the fluorine atoms, each fluorinated oil or amphile molecule gives one sharp singlet 19F NMR signal.

Resistance of polyfluorinated complete esters of polyhydric alcohols to thermal oxidation: Comparison with nonfluorinated analogs

Complete esters of pentaerythritol, trimethylolpropane, and 2,2-dimethyl-1,3-propanediol with polyfluorinated carboxylic acids were prepared by esterification. As determined by differential thermal gravimetric analysis in air, the resistance of the esters to thermal oxidation decreases in going from pentaerythritol derivatives to those of trimethylolpropane and then to those of 2,2-dimethyl-1,3-propanediol. The compounds synthesized surpass their nonfluorinated analogs in the resistance to thermal oxidation.

Synthesis of a Nonavalent Mannoside Glycodendrimer Based on Pentaerythritol

A nonavalent glycodendrimer bearing terminal alpha-d-mannopyranoside units has been synthesized with a convergent approach. Terminal trivalent mannoside dendrons bearing p-halophenyl ethers were prepared by glycosylation of pentaerythritol derivatives having three 2-hydroxyethyl ether substituents. Two efficient routes were developed for the synthesis of the pentaerythritol-based core (17), which has three terminal propargyl ethers. Conditions were found under which the triple Sonogashira coupling reaction of the dendron and the tri-O-propargyl ether (17) proceeded efficiently. The product was deprotected and it and precursors were fully characterized by NMR spectroscopy and FT-ICR mass spectrometry.

Pentaerythritol as the Core of Multivalent Glycolipids: Synthesis of a Glycolipid with Three SO3Lea Ligands

A glycolipid containing three SO(3)Le(a) ligands was synthesized with pentaerythritol as the core. The glycolipid was used to prepare glycoliposomes that showed stability similar to that of DSPC liposomes without glycolipid. The easily prepared derivatives of pentaerythritol proved to be useful scaffolds for multivalent displaying of carbohydrates in the form of glycolipids and clustered glycoliposomes. [structure: see text]

Flammability and thermal degradation of flame retarded polypropylene composites containing melamine phosphate and pentaerythritol derivatives

The flammability of polypropylene (PP) composites containing intumescent flame retardant additives, i.e. melamine phosphate (MP) and pentaerythritol (PER), dipentaerythritol (DPER) or tripentaerythritol (TPER) was characterized by limiting oxygen index (LOI), UL 94 and the cone calorimeter, and the thermal degradation of the composites was studied using thermogravimetric analysis (TG) and real time Fourier transform infrared (RTFTIR). It has been found that the PP composite containing only MP does not show good flame retardancy even at 40% additive level. Compared with the PP/MP binary composite, the LOI values of the PP/MP/PER (PP/MP/DPER or PP/MP/TPER) ternary composites at the same additive loading are all increased, and UL 94 ratings of most ternary composites studied are raised to V-0 from no rating (PP/MP). The cone calorimeter results show that the heat release rate and smoke emission of some ternary composites decrease in comparison with the binary composite. It is noted from the TG data that initial decomposition temperatures of ternary composites are lower than that of the binary composite. The RTFTIR study indicates that the PP/IFR composites have higher thermal oxidative stability than the pure PP.

60]Fullerene Diol Issued from Pentaerythritol Derivatives.

Abstract A new [60]fullerene diol is synthesized in good yield, in two steps starting from reaction of C 60 2− anion with the benzylideneacetal derived from 2,2-bis(iodomethyl)-1,3-propanediol. The corresponding [60]fullerene bis-mesylate is also formed in a similar way starting from bis-iodo bis-mesylate compound in the same series. The scope of this fullerene diol in synthesis is exemplified by its easy esterification with 4-formyl benzoyl chloride.

60]Fullerene diol issued from pentaerythritol derivatives

A new [60]fullerene diol is synthesized in good yield, in two steps starting from reaction of C 60 2− anion with the benzylideneacetal derived from 2,2-bis(iodomethyl)-1,3-propanediol. The corresponding [60]fullerene bis-mesylate is also formed in a similar way starting from bis-iodo bis-mesylate compound in the same series. The scope of this fullerene diol in synthesis is exemplified by its easy esterification with 4-formyl benzoyl chloride.

Synthesis of Functionalized Derivatives of Pentaerythritol.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Synthesis of Functionalised derivatives of Pentaerythritol

The synthesis of functionalised derivatives of pentaerythritol has been attempted by the reaction of 1 with different aldehydes and nucleophilic reagents; the activity of various derivatives against hepatitis B virus has been studied.