97 research outputs found
trans-(2-Benzoylpyridine-κ2 N,O)dichlorido[2-(2-pyridylcarbonyl)phenyl-κ2 C 1,N]iridium(III) dichloromethane solvate
The title compound, [Ir(C12H8NO)Cl2(C12H9NO)]·CH2Cl2, which was obtained from the reaction of iridium(III) chloride trihydrate and 2-benzoylpyridine, contains an IrIII atom coordinated by two N, one O, one C and two Cl atoms in trans positions, forming a distorted octahedral environment. The solvent molecule CH2Cl2 is disordered over two positions with an occupancy of 0.8:0.2
Dichlorido{(E)-2,4,6-trimethyl-N-[phenyl(2-pyridyl)methylidene]aniline-κ2 N,N′}palladium(II)
The title complex, [PdCl2(C21H20N2)], contains a PdII atom in a slightly distorted square-planar coordination environment defined by two N atoms from one 2,4,6-trimethyl-N-[phenyl(2-pyridyl)methylidene]aniline ligand and two Cl atoms, forming a five-membered ring (N—Pd—N—C—C)
Pilot Scheme of Health Policy in Stroke Adjuvant Acupuncture Therapy for Acute and Subacute Ischemic Stroke in Taiwan
To reduce the health care burden of strokes, the Taiwan Department of Health launched the Pilot Scheme of the Health Policy in Stroke Adjuvant Acupuncture Therapy (HPSAAT) in 2006. This cross-sectional, hospital-based, match-controlled study at Chang Gung Memorial Hospital-Kaohsiung Medical Center during 2006∼2008 retrospectively evaluated the clinical characteristics of acute and subacute ischemic stroke patients who electively joined the HPSAAT. The study also evaluated the safety and clinical benefits of adjuvant acupuncture in treating acute and subacute ischemic stroke patients.
Twenty-six HPSAAT participants and 52 age-sex matched random controls were enrolled. The stroke baseline of the HPSAAT participants was more severe than the non-HPSAAT controls. Although the stroke severity closely correlates to mortality and comorbidity, this study noted no significant complications in the HPSAAT participants during the acupuncture treatment course. Adjuvant acupuncture was considered safe at the acute and subacute stages of ischemic stroke. Due to uneven baseline severity, the clinical benefits in reducing neurological deficits and functional recovery were not concluded in this study
Six-membered ring systems: with O and/or S atoms
A large variety of publications involving O- and S-6-membered ring systems
have appeared in 2017. The importance of these heterocyclic compounds
is highlighted by the huge number of publications on the total
synthesis of natural oxygen derivatives and of other communications
dedicated to synthetic derivatives.
Reviews on stereoselective organocatalytic synthesis of tetrahydropyrans
(17EJO4666), of tetrahydropyrans and their application in total synthesis of
natural products (17CSR1661), on the synthesis of the less thermodynamically
stable 2,6-trans-tetrahydropyrans (17S4899), on enantioselective
synthesis of polyfunctionalized pyran and chromene derivatives
(17TA1462), and on enantioselective and racemic total synthesis of
camptothecins, including the formation of their pyran-2-one ring
(17SL1134), have appeared.
Advances in the transition metal-catalyzed synthesis of pyran-2/4-ones
(17TL263), N-heterocyclic carbene (NHC)-catalyzed achiral synthesis of
pyran-2-one, coumarin and (thio)chromone derivatives (17OBC4731), on
the synthesis and transformation of 2H-pyran-2-ones (17T2529) and
2-styrylchromones (17EJO3115) into other heterocyclic compounds, have
been surveyed. The strategies to build up the tetrahydropyranyl core of
brevisamide (17H(95)81) and the reactions of ketyl radicals, generated from
carbonyl derivatives under transition-metal photoredox-catalyzed conditions,
leading to isochromen- and chroman-type compounds (17CC13093) were
disclosed. Developments in the synthesis of pentafluorosulfanyl(chromene
and coumarin) derivatives (17TL4803), photoswitchable D9-tetrahydrocannabinol
derivatives (17JA18206), and aminobenzopyranoxanthenes
with nitrogen-containing rings (17JOC13626) have been studied.info:eu-repo/semantics/publishedVersio
International Consensus Statement on Rhinology and Allergy: Rhinosinusitis
Background: The 5 years since the publication of the first International Consensus Statement on Allergy and Rhinology: Rhinosinusitis (ICAR‐RS) has witnessed foundational progress in our understanding and treatment of rhinologic disease. These advances are reflected within the more than 40 new topics covered within the ICAR‐RS‐2021 as well as updates to the original 140 topics. This executive summary consolidates the evidence‐based findings of the document. Methods: ICAR‐RS presents over 180 topics in the forms of evidence‐based reviews with recommendations (EBRRs), evidence‐based reviews, and literature reviews. The highest grade structured recommendations of the EBRR sections are summarized in this executive summary. Results: ICAR‐RS‐2021 covers 22 topics regarding the medical management of RS, which are grade A/B and are presented in the executive summary. Additionally, 4 topics regarding the surgical management of RS are grade A/B and are presented in the executive summary. Finally, a comprehensive evidence‐based management algorithm is provided. Conclusion: This ICAR‐RS‐2021 executive summary provides a compilation of the evidence‐based recommendations for medical and surgical treatment of the most common forms of RS
Synthesis, Characterization and Catalytic Studies of EDBP Supported Lithium, Sodium, Magnesium and Zinc Complexes: Efficient Catalysts for Ring-Opening Polymerization of e-Caprolactone and L-Lactide and Anionic Polymerization of Methyl Methacrylate
Several novel zinc and magnesium aryloxides, [(EDBP)Zn(THF)]2 (1), [(EDBP)Mg(Et2O)]2 (2), and [(EDBP)Mg(THF)]2 (3), have been synthesized by the reaction of 2,2¢-ethylidenebis(4,6-di-tert-butylphenol) (EDBP-H2) with ZnEt2 or MgnBu2 in diethyl ether (Et2O) or tetrahydrofuran (THF), respectively. Experimental results show that 1-3 efficiently catalyze the ring-opening polymerization (ROP) of e-caprolactone (e-CL) and L-lactide (L-LA) in a controlled fashion, yielding polymers with very narrow polydispersity indexes (PDI) in a wide range of monomer-to-initiator ratios. The reaction of EDBP-H2 with nBuLi in THF, Et2O or hexane, gives [(EDBP-H)Li(THF)3] (4), [(EDBP-H)Li(Et2O)3] (5) or [(EDBP-H)Li]3 (6), respectively. However, the reaction of EDBP-H2 with nBuLi in the presence of benzyl alcohol (BnOH) in Et2O or THF produces compound [(EDBP-H)Li(BnOH)]2 (7) or [(EDBP-H)Li(BnOH)(THF)2] (8), respectively. Further reaction of 7 with excess of THF produces 8. Alternatively, 8 can also be prepared by the reaction of benzyl alcohol with 4 in toluene. Experimental results show that 7 and 8 efficiently initiate the ROP of L-lactide in a controlled fashion, yielding polymers with very narrow polydispersity indexes in a wide range of monomer-to-initiator ratios. Moreover, the reaction of EDBP-H2 with 2.2 equiv nBuLi in Et2O affords [(EDBP)Li2(Et2O)]2 (9). Moreover, block copolymers, polystyrene-b-poly(L-lactide), have also been prepared from the ring-opening polymerization of L-latide catalyzed by 2 and 4 using polystyrene as a macroinitiator.
The unusual lithium n-butylmagnesium [(EDBP)Mg(m2-nBu)Li(Et2O)]2 (10), sodium n-butylmagnesium [(EDBP)Na(Et2O)MgnBu]2 (13), lithium ethylzinc [(EDBP)Zn(THF)]2[(m2-C2H5)Li(THF)] (14) and lithium-magnesium enolate, {(EDBP)Mg[m2-OC(Mes)CH2]Li(Et2O)}2 (11), and the sodium aggregate, [(EDBP)Na2]4 (12), have been synthesized and structurally characterized. Among them, 10, 11, 13 and 14 have been used as initiators for the polymerization of methyl methacrylate. The dimeric lithium n-butylmagnesium complex 10 was obtained from the reaction of [(EDBP)Li(Et2O)3] (5) with a stoichiometric amount of MgnBu2. Alternatively, 10 can also be prepared by the reaction of [(EDBP)Mg(Et2O)]2 (2) with a stoichiometric amount of nBuLi in Et2O. Furthermore, the reaction of 10 with 2¢,4¢,6¢-trimethylacetophenone (MesC(O)CH3, Mes = 2,4,6-Me3C6H2) produces 11. Reaction of EDBP-H2 with excess sodium metal in Et2O furnishes compound 12. In the presence of a stoichiometric amount of MgnBu2 in Et2O, 12 can be converted to the dimeric sodium-magnesium mixed-metal complex [(EDBP)Na(Et2O)MgnBu]2 (13). Moreover, 14 can be obtained by the reaction of [(EDBP)Li(THF)3] (4) with a stoichiometric amount of ZnEt2. Experimental results show that 10, 11, 13 and 14 efficiently initiate the anionic polymerization of methyl methacrylate.Abstract…………………………………………………………………....1
Chapter 1. Introduction
Biodegradable Polymers……………………………………....3
Metal Complexes Supported by Salen Ligands………………5
Metal Complexes Supported by Biphenol Ligands…………...8
References…………………………………………………...11
Chapter 2. Zinc, Magnesium and Lithium Complexes
Introduction……………………………………………....….15
Results and Discussion………………………………………17
Synthesis and Spectroscopic Studies of Compounds1-9…....17
Molecular Structure Studies of 1-3………………………….20
Molecular Structure Studies of 4 and 6-9……………….…..24
ROP of e-CL Using Complex 1 as Initiator………………...33
ROP of L-LA Using Complexes 1-3 as catalysts………......37
Proposed Mechanism for ROP of L-LA Catalyzed by 1-3...44
ROP of L-LA Using Complexes 7 and 8 as Initiators…….....46
Proposed Mechanism for ROP of L-LA Catalyzed by 7…...50
Summary………...…………………………..……………....52
Experimental Section…………………………………..…....52
References………………………………..………………….58
Chapter 3. Application for the Synthesis of PS-b-PLLA
Introduction………………………………………………….62
Preparation of 4-Hydroxyl-TEMPO-terminated Polystyrene
…………………………………………………………….…64
Synthesis of Polystyrene-Poly(L-lactide) Diblock Copolymer
……………………………………………………....…...….67
Summary…...…………………………………………..…....70
Experimental Section…………………………………..…....70
References………………………………..………...………..71
Chapter 4. Mixed- Metal Complexes
Introduction………………………………………………….73
Results and Discussion……………………………………....81
Synthesis and Spectroscopic Studies of 10-14……………...81
Molecular structure studies of 10-14………………………..83
Polymerization of MMA Using Complexes 10, 11, 13 and 14 as Initiators…………………………………………………..93
Summary………………………….…..……………………..97
Experimental Section………………………………………..97
References………………………………………………….100
Chapter 5. Conclusion………………………………………………….106
Chapter 6. General Informations
NMR Spectra…………………………………....………….109
Gel Permeation Chromatography (GPC)…………………..109
X-ray Crystallographic Studies………..…..…………...….109
Differential Scanning Calorimeter (DSC)…………...…......110
Materials…………………………………………………....110
Reference…………………………………..….……….…...111
Catalog of Scheme, Figures and Tables
Scheme 1…………………………………………………………….……18
Scheme 2……………………………………………………………….…45
Scheme 3……………………………………………………………….…51
Scheme 4………………………………………………………………….66
Scheme 5………………………………………………………………….82
Scheme 6……………………………………………………………...…108
Figure 1…………………………………………………………………....21
Figure 2…………………………………………………………………....21
Figure 3……………………………………………………………………25
Figure 4……………………………………………………………………25
Figure 5……………………………………………………………………29
Figure 6……………………………………………………………………29
Figure 7……………………………………………………………………32
Figure 8…………………………………………………………………....36
Figure 9……………………………………………………………………37
Figure 10…………………………………………………………………..42
Figure 11…………………………………………………………………..43
Figure 12…………………………………………………………………..49
Figure 13……………………………………………………………….….49
Figure 14…………………………………………………………………..69
Figure 15…………………………………………………………………..69
Figure 16…………………………………………………………………..85
Figure 17…………………………………………………………………..86
Figure 18…………………………………………………………………..86
Figure 19…………………………………………………………………..87
Figure 20…………………………………………………………………..87
Figure 21…………………………………………………………………..96
Table 1…………………………………………………………………….22 Table 2…………………………………………………………………….22
Table 3…………………………………………………………………….23
Table 4…………………………………………………………………….26
Table 5…………………………………………………………………….26
Table 6…………………………………………………………………….27
Table 7…………………………………………………………………….30
Table 8…………………………………………………………………….30
Table 9…………………………………………………………………….31
Table 10…………………………………………………………………...33
Table 11…………………………………………………………………...35
Table 12…………………………………………………………….…..…40
Table 13………………………………………………………………...…41
Table 14……………………………………………………….…………..48
Table 15………………………………………………………………...…66
Table 16………………………………………………………………...…68
Table 17………………………………………………………………...…88
Table 18………………………………………………………………..….88
Table 19………………………………………………………………...…89
Table 20………………………………………………………………..…90
Table 21………………………………………………………………..…91
Table 22………………………………………………………………..…92
Table 23………………………………………………………………..…9
Reactions of 2,2 '-(2-methoxybenzylidene)bis(4-methyl-6-tert-butylphenol) with trimethylaluminum: Novel efficient catalysts for "living" and "immortal" polymerization of epsilon-caprolactone
A sterically hindered biphenol 2,2'-(2-methoxybenzylidene)bis(4-methyl-6-tert-butylphenol) (MEBBP-H-2) (1) has been prepared by the reaction of o-anisaldehyde with 2-tert-butyl-4-methylphenol in the presence of a catalytic amount of benzenesulfonic acid. Further reaction of compound 1 with a stoichiometric amount of Me3Al in tetrahydrofuran produces a four-coordinated monomeric aluminum complex [(MEBBP)AlMe(THF)] (2). [(MEBBP)Al(mu-OBn)](2) (3) can then be synthesized by the reaction of 2 with I mol equiv of benzyl alcohol at ambient temperature. Compound 3 has demonstrated highly efficient activities toward ring-opening polymerization of E-caprolactone. The "living" and the "immortal" character of 3 has paved a way to synthesize as much as 256-fold polymer chains of poly(epsilon-caprolactone) with a very narrow polydispersity index in the presence of a small amount of initiator. In addition, the polystyrene-b-poly(epsilon-caprolactone) copolymer has also been prepared using polystyrene containing a hydroxy chain end as an initiator in the presence of 2
Development of a Computerized Adaptive Testing System for Assessing 5 Functions in Patients with Stroke: A Simulation and Validation Study
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