Bis{1-[(E)-(2-methyl­phen­yl)diazen­yl]-2-naphtho­lato}palladium(II)

In the title compound, [Pd(C17H13N2O)2], the PdII atom is tetra­coordinated by two N atoms and two O atoms from two bidentate methylphenyl­diazenylnaphtolate ligands, forming a square-planar complex. The two N atoms and two O atoms around the PdII atom are trans to each other (as the PdII atom lies on a crystallographic inversion centre) with O—Pd—N bond angles of 89.60 (11) and 90.40 (11)°. The distances between the PdII atom and the coordinated O and N atoms are 1.966 (3) and 2.009 (3) Å, respectively

Synthesis , Spectroscopic Properties and Metal Complexation of Porphyrin-Bipyridine Conjugates

利用 Sonogashira cross-coupling 的方法合成出一系列紫質－雙吡啶共軛體：包含有直線型 (12) ，單邊型 (17) ，和垂直型 (23) 三種。在化合物 (17) 和 (23) 與金屬 (Ag+, Fe2+, Co2+, Ni2+, Cu2+, Zn2+) 錯合性質的研究中，可以得知以雙吡啶 (Bipyridine) 為芽基可以成功的螯合金屬，觀察其 Soret band 的變化，因為金屬離子的拉電子作用透過 C≣C 三鍵將電子效應傳遞到紫質上，所以 UV-Visible 吸收度會明顯的變寬並且有紅位移的現象，並利用 Simulation 和SPECFIT 軟體計算求出金屬錯合的形成常數 (β) 。在分析化合物 (17) 錯合性質研究中，當金屬離子為 Co2+ 或 Zn2+ 時在濃度較低時，可和紫質形成 ML 及 ML2 形式的錯合物 (stability constants: logβ1=7.40, logβ2=12.22 for Co2+ ; logβ1=7.28, logβ2=12.27 for Zn2+)，但當再加入更多的金屬離子時，則只能行成 ML 形式的錯合物，若金屬離子為 Fe2+, Ni2+, Cu2+ 時則只以 ML 形式存在 (stability constants: logβ1=7.38 for Fe2+ ; logβ1=8.06 for Ni2+; logβ1=8.26 for Cu2+)。 在分析化合物 (23) 錯合性質研究中，當金屬離子與紫質形成錯合物時，第一對雙吡啶和金屬錯合後，並不影響到第二對雙吡啶與金屬錯合的能力。Porphyrin-bipyridine conjugates 12, 17, 23, have been successfully synthesized by using Sonogashira cross-coupling reaction. These conjugates are capable of coordination with various metal ions. Upon coordination with metal ions, the UV-visible spectra show significant red shift and peak-broadening of soret band and Q bands. The stability constants of porphyrin-bibyridine conjugates with metal ions were calculated by SPECFIT software. The stability constants of porphyrin 17 are calculated to be logβ1 =7.40 (1:1 complex) and logβ2 =12.22 (1:2 complex) for Co2+, and logβ1 =7.28 and logβ2 =12.22 for Zn2+. The coordination of 17 with Fe2+, Ni2+, and Cu2+ forms the corresponding 1:1 complex with stability constants of logβ1 =7.38, logβ1 =8.06, and logβ1 =8.26 , respectively .The UV-Visible titration of porphyrin 23 with metal ions show that the two bipyridine units independently coordinate with metal ions.中文摘要…………………………………………………………..……Ⅱ 英文摘要…………………………………………………………..……Ⅳ 第一章：緒論 1-1. 紫質的簡介..…………………………….……………………..1 1-2. 雙吡啶的簡介…………...…………………………...………10 1-3.金屬螺旋超分子……………………………………………..….14 1-3.1.單股螺旋錯合物…..………………………………………….16 1-3.2. 雙股螺旋錯合物………………………………………………18 1-4. 分子設計……..…………………………………………………24 參考文獻………….…………………………………………………….35 第二章 : 實驗部分 2-1.1 實驗前處理…...………………………………………………40 2-1.2 藥品廠商…...…………………………………………………40 2-1.3 實驗儀器與軟體….………………………….…………………42 2-2. 合成步驟….....………………………………………………43 參考文獻.............................................67 第三章 : 結果與討論 3-1. 合成部分…...…………………………………………………68 3-2. UV/Visible 光譜滴定法………………………………...……74 3-3.NMR及MS光譜分析…..…………….…………..……….....103 3-4.其他測量穩定常數的方法……………………….……….…….108 參考文獻……………...………………….……………………..……109 第四章 : 結論………………………………………………………...110 附錄 NMR光

Synthesis, Characterization and Structural Determination of Lithium and Magnesium Complexes Stabilized by New Ancillary Bulky Ligands BCP from Application of Lactide Polymerization: Nanostructure and Nanotemplate from Self-Assembly of Biodegradable Block Copolymers

Novel and soluble coordinated lithium aggregates have been synthesized and structurally well characterized. They are often electron deficient and are usually multinuclear-multiligand entities hold together by mu-type of bonds. Factors affecting their aggregation will be discussed in details. The reaction of [(EDBP)Li2]2[(nBu)Li(0.5Et2O)]2 (1) (EDBP-H2: 2,2'-ethylidene-bis(4,6-di-tert-butylphenol)) with one equivalent of ROH in toluene gives [(EDBP)Li2]2[(OR)Li]2 (2: R = Bn; 3: R = CH2CH2OEt; 4: R = nBu). In the presence of three equiv THF, the hexa-nuclear compound 1 slowly decomposes to an unusual penta-nuclear lithium complex, [(EDBP)2Li4(THF)2][( nBu)Li] (5). Further reaction of 5 with ROH gives [(EDBP)2Li4(THF)3][(OR)Li] {R = Bn (6), nBu (7), CH2CH2OEt (8)} without a drastic change in its skeleton. Compounds [(EDBP)Li2(HMPA)2][(OBn)Li(HMPA)] (9), [(EDBP)2Li4(THF)][(OCH2CH2OEt)Li]2 (10) and [(EDBP)2Li4(OCH2CH2OEt)(HMPA)]-[Li(HMPA)4]+ (11) (HMPA: hexamethylphosphoramide) can be obtained by the reaction of lithium alkoxide 2, 3 and 4 with “oxygen-donor solvent,” such as THF and HMPA respectively, to gives rearranged and solvated products. Among them, compound 8 has shown great reactivity toward ring-opening polymerization of L-lactide yielding polymers with very low polydispersity indexes in a wide range of monomer-to-initiator ratios. The reaction of 1 with 2 equiv of 2,4,6-trimethylacetophenone in toluene can also obtain a lithium enolate 12 without any drastic change in skeleton. In the presence of excess THF furnishes a lithium enolate, 13, without EDBP backbone. Compound 12 represents the first example of a well-defined lithium enolate initiator for highly isoselective polymerization of MMA under relatively mild reaction conditions. Besides, four novel lithium and magnesium complexes, [(EDBPBS)2Li2(THF)] (16); [(EDBPBS)Li(THF)2] (17); [(BHPMP-TS)Mg(THF)]2 (18); [(BHPMP-TS)2Mg2(THF)3]2 (19), stabilized by two new ancillary ligands (EDBP-BS: 2,4-di-tert-butyl-6-(1-(3,5-di-tert-butyl- 2-hydroxyphenyl)ethyl)phenyl benzenesulfonate; BHPMP-TS: 4-tert-butyl-2,6-bis(3,5-di-tert-butyl-2-hydroxybenzyl)phenyl-4-methyl- benzenesulfonate. In the presence of THF, 17 and 18 can also be prepared directly by 16 and 19 respectively, followed by rearrangement and solvation. More importantly, a combination of free radical polymerization and ring-opening polymerization of lithium alkoxide macroinitiator enables us to synthesize block copolymer, PS-b-PLLA. According to the results of TEM, SAXS and FESEM, these block copolymers show a well-defined material system with self-assembling nanostructures, including sphere, hexagonal cylinder, lamelle and hexagonally packed nanohelix.Contents Abstract…………………………………………………………………....1 Chapter 1. Introduction Biodegradable Polymers……………………………………...3 Metal Complexes Supported by Salen Ligands………………7 Metal Complexes Supported by Biphenolate Ligands………..9 References…………………………………………………...13 Chapter 2. Synthesis, Characterization and Structural Determination of Polynuclear Lithium Aggregates and Factors Affecting Their Aggregation Introduction……………………………………………………17 Results and Discussion………………………………………19 Synthesis and characterization of Mixed-Ligand Lithium Aggregates……………………………………………………19 Synthesis and characterization of Lithium Enolate Complexes…………………………………………….…….22 Molecular Structure Studies of 5, 12 and 13…………….…..24 Ring-Opening Polymerization of L-Lactide Using Complex 8 as an Initiator………………………………………………..28 Anionic Polymerization of MMA Using Complexes 12 as Initiator……………………………………………………...31 Summary………...…………………………………………....32 Experimental Section………………………………………....33 References…………………………………………………….38 Chapter 3. Synthesis, Characterization and Structural Determination of Lithium and Magnesium Complexes Stabilized by New Ancillary Ligands Introduction………………………………………………….45 Results and Discussion………………………………………52 Synthesis and characterization of p-substituted- benzenesulfonylate ligands………………………………....52 Synthesis and characterization of lithium and magnesium complexes supported by EDBP-BS and BHPMP-TS ligands……………………………………………………...53 Molecular Structure Studies of 16-19………………………55 Summary…...…………………………………………..…....59 Experimental Section…………………………………..…....60 References………………………………..………...………..63 Chapter 4. BCP from Application of Lactide Polymerization: Nanostructure and Nanotemplate from Self-Assembly of Biodegradable Block Copolymers Introduction………………………………………………….68 Preparation of 4-Hydroxyl-TEMPO-terminated Polystyrene………………………………………………….71 Synthesis of Polystyrene-Poly(L-lactide) Diblock Copolymer…………………………………………………..73 Morphologies of PS-b-PLLA……………..………..……....80 Summary………………………….…..……………………..85 Experimental Section………………………………………..86 References…………………………………………………...87 Chapter 5. Conclusion………………………………………………….90 Chapter 6. General Informations NMR Spectra…………………………………....………….92 Gel Permeation Chromatography (GPC)……………….…..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

A highly efficient initiator for the ring-opening polymerization of lactides and epsilon-caprolactone: A kinetic study

A trinuclear zinc alkoxide [{(BDI-OMe)Zn(mu-OBn)}(2)Zn(mu-OBn)(2)] (1) and a homoleptic zinc complex [(BDI-OMe)(2)Zn] (2) have been prepared by the addition of benzyl alcohol to a mixture of BDI-OMe-H with Et2Zn. Compound 1 has been employed as an initiator for ring-opening polymerization of lactides and epsilon-caprolactone. The highly efficient initiator of the zinc complex shown in the polymerization process enabled us to synthesize the PLA at ambient temperature, yielding PLA with well molecular control and narrow molecular weight distribution in a very short period of time. The polymerization kinetics were studied with [LA](0)/[1] = 200/1 and [LA](0) = 0.5 M at 25 degrees C. Experimental results indicate a second-order dependency on [LA] (k(obs) = 0.033 M-1 s(-1)). Moreover, a first-order dependency in [1] is indicated of k(obs) vs [Initiator], with a slope equal to the first-order rate constant k = 12.2 M-2 s(-1). Furthermore, the heterotactic PLA with Pr up to 83% can be achieved in a mixed solvent of CH2Cl2 and THF at -35 degrees C. However, according to polymerization kinetic studies of CL, a first-order dependency on [CL] and [1] is observed for ROP of epsilon-caprolactone

tert-Butyl 2-sulfanylidene-2,3-dihydro-1H-imidazole-1-carboxylate

In the title molecule, C8H12N2O2S, the imidazole ring forms a dihedral angle of 5.9 (2)° with the mean plane of the carboxylate group. In the crystal, molecules are linked by pairs of N—H...S hydrogen bonds, forming inversion dimers