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81.
Joshua Ayoola Obaleye Mino R. Caira Adedibu C. Tella 《Journal of chemical crystallography》2007,37(10):707-712
Abstract A novel polymeric zinc(II) complex of quinine, [chlorosulphato (2-ethenyl)-4-azabicyclo[2.2.2]oct-5-ylium-(6-methoxyquinolin-4-yl)
methanol zinc(II)] has been synthesized and characterized. Single-crystal X-ray diffraction analysis of the complex (C20H25ClN2O6SZn) revealed that quinine forms a zigzag coordination polymeric complex with Zn(II) of extended chains –ZnCl–O–SO2–O–Zn–O–SO2–O–ZnCl–. The crystals are monoclinic, space group C2 with a = 20.5035(5), b = 9.7943(2), c = 11.7814(4) ?, β = 96.578(2)°, Z = 4, V = 2350.3(1) ?3. The complex exhibits a tetrahedral geometry. Each Zn(II) centre is thus coordinated to an O atom from each of two sulphate
bridges, a Cl atom and quinoline atom N(4) of the quinine moiety. The second quinuclidine nitrogen in the quinine is protonated.
In the crystal, there is linkage of two polymeric chains related by a twofold rotation axis, resulting in a bilayer. The linking
is achieved by hydrogen bonding from the quinine cation which provides two donors (–OH, N+–H), to oxygen atoms of sulphate groups which act as acceptors.
Graphical Abstract The new polymeric zinc(II) complex of quinine, [chlorosulphato (2-ethenyl)-4-azabicyclo[2.2.2]oct-5-ylium-(6-methoxy quinolin-4-yl)
methanol Zinc(II)] has been synthesized and structurally characterized The compound was characterized by IR spectroscopy,
elemental analysis and X-ray diffraction. X-ray analysis showed that quinine forms a zigzag coordination polymeric complex
with Zn(II) of extended chains –ZnCl–O–SO2–O–Zn–O–SO2–O–ZnCl–.
相似文献
82.
Takashi Mino Miho Ishikawa Kenji Nishikawa Kazuya Wakui Masami Sakamoto 《Tetrahedron: Asymmetry》2013,24(8):499-504
The palladium-catalyzed asymmetric allylic alkylation of indoles with 1,3-diphenyl-2-propenyl acetate using P/N-type ligands such as N-aryl indole, C–N bond axially chiral aminophosphine (aS)-L4, gave the desired products 1 in good yields and with moderate to high enantioselectivities (up to 90% ee). 相似文献
83.
84.
Yuta Saga Yuka Mino Shin-ichi Kawaguchi Daoqing Han Akiya Ogawa Li-Biao Han 《Tetrahedron: Asymmetry》2017,28(1):84-89
A variety of P-stereogenic organophosphorus compounds can be readily prepared by stereoretentive addition. The PMe3-catalyzed addition of optically active (?)MenthylO(Ph)P(O)H compounds to electron deficient alkenes occur stereospecifically, to produce the corresponding P-stereogenic adducts in high yields. By simply removing the volatiles under vacuum, spectroscopically pure products can be obtained. The present method provides a salt-free clean process for the preparation of P-chiral organophosphorus compounds. 相似文献
85.
Dr. Graham N. Newton Dr. Norihisa Hoshino Dr. Takuto Matsumoto Dr. Takuya Shiga Prof. Motohiro Nakano Prof. Hiroyuki Nojiri Prof. Wolfgang Wernsdorfer Prof. Yuji Furukawa Prof. Hiroki Oshio 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(40):14205-14212
Here we report the synthesis, structure and detailed characterisation of three n‐membered oxovanadium rings, Nan[(V=O)nNan(H2O)n(α, β, or γ‐CD)2]?m H2O (n=6, 7, or 8), prepared by the reactions of (V=O)SO4?x H2O with α, β, or γ‐cyclodextrins (CDs) and NaOH in water. Their alternating heterometallic vanadium/sodium cyclic core structures were sandwiched between two CD moieties such that O‐Na‐O groups separated the neighbouring vanadyl ions. Antiferromagnetic interactions between the S=1/2 vanadyl ions led to S=0 ground states for the even‐membered rings, but to two quasi‐degenerate S=1/2 states for the spin‐frustrated heptanuclear cluster. 相似文献
86.
The phytoalexin psoralen (7H-furo[3,2-g][1]benzopyran-7-one) has been included in heptakis(2,3,6-tri-O-methyl)-β-cyclodextrin (TRIMEB) to yield a solid crystalline complex of formula TRIMEB-psoralen-H2O. Its X-ray structural elucidation provides an accurate model for cyclodextrin–furocoumarin interaction. Thermal analysis (hot stage microscopy, differential scanning calorimetry, thermogravimetry) indicated complex dehydration in the range 40–100°C followed by melting at 137.1°C. The X-ray analysis showed that the elongated guest molecule induces elliptical distortion in the host molecule, with which it interacts via C-H ?O hydrogen bonding and hydrophobic interactions. The host molecule adopts a very similar conformation to that in the isostructural complex with l-menthol as guest. Water molecules bridge symmetry-related TRIMEB molecules by hydrogen bonding. 相似文献
87.
Mino R. Caira Marcel Mirel Popa Constantin Draghici Loredana Barbu Denisa Dumitrescu Florea Dumitrascu 《Tetrahedron letters》2014
7,8,9,10-Tetrahydropyrrolo[2,1-a]isoquinolines were obtained by 1,3-dipolar cycloaddition reactions of their corresponding N-ylides with olefinic (acrylonitrile) and symmetrical or non-symmetrical acetylenic dipolarophiles (methyl/ethyl propiolate, dimethyl acetylenedicarboxylate). Also, stable 5,6,7,8-tetrahydroisoquinolinium dicyanomethylide was isolated and characterized by X-ray diffraction analysis. 相似文献
88.
Takumi Nakamura Kazuma Ban Dr. Yasushi Yoshida Prof. Dr. Takashi Mino Prof. Dr. Yoshio Kasashima Prof. Dr. Masami Sakamoto 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(66):16338-16341
Asymmetric synthesis was performed by combining the photochemical reaction of an achiral substrate followed by crystallization-induced deracemization. The results indicated that a fused indoline produced by photochemical intramolecular δ-hydrogen abstraction and cyclization of N-(5-chloro-2-methylphenyl)phthalimide crystallized as a racemic conglomerate. Since this substrate has an aminal skeleton, racemization involving a ring-opening and ring-closing equilibrium process occurred under suitable conditions. Efficient racemization was observed in acetone containing a catalytic base, 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU). Crystallization-induced dynamic deracemization by Viedma ripening from racemic indoline was performed with an excellent enantioselectivity of 99 % ee. Furthermore, one-pot asymmetric synthesis of the indoline was achieved by the photochemical reaction of achiral phthalimide followed by continuous attrition-enhanced deracemization converging to 99 % ee of enantiomeric crystals. This is the first example of asymmetric expression and amplification by photochemical hydrogen abstraction and crystallization-induced dynamic deracemization. 相似文献
89.
Trost BM Malhotra S Mino T Rajapaksa NS 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(25):7648-7657
The asymmetric acylation of meso-2-substituted-1,3-propanediols by using an amphoteric chiral dinuclear zinc catalyst is described. It is has been demonstrated that both 2-alkyl- and 2-aryl-1,3-propanediols can be desymmetrized in high yields and enantioselectivities by using the same family of ligands. Given that both antipodes of the chiral catalyst are available, both enantiomers of the desymmetrized product can be obtained from the same starting material. The synthetic utility of the desymmetrized products has been demonstrated by the synthesis of several chiral building blocks with high enantiomeric purities. 相似文献
90.
Sakamoto M Kawanishi H Mino T Fujita T 《Chemical communications (Cambridge, England)》2008,(18):2132-2133
Optically active beta-lactams were synthesized via photochemical intramolecular gamma-hydrogen abstraction reaction of thioimides involving a highly-controlled chiral-memory effect. 相似文献