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71.
Olaf Böge Eckhart Nietzschmann Joachim Heinicke 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):25-29
Abstract 2-Bromoaryloxy-chloromethyldiorganosilanes react with sodium in a one-pot-reaction via metallation, [1,3]-carbanionic rearrangement and cyclization to give diorgano-1,3-benzoxasilolenes. The title compounds have been characterized by n.m.r. spectroscopic data and an alternative independent synthesis. 相似文献
72.
S. R. Jayapradha S. Muthusubramanian 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):32-38
Abstract The synthesis of a new set of 2,3,4,5-substituted isoxazolidines having a sulfur containing heterocyclic moiety has been described. The structural features of the compounds have been analyzed by 1H and 13C NMR spectroscopy as well as by single crystal X-ray studies. [Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental resource: .cif file.] 相似文献
73.
A. R. Suresh Babu 《合成通讯》2013,43(3):451-458
2‐Arylidene‐1,3‐indanediones undergo regioselective 1,3‐dipolar cycloaddition with the azomethine ylide generated from acenaphthenequinone and sarcosine to afford a rare class of complex dispiropyrrolidines in good yield. Single‐crystal X‐ray crystal analysis of one of the products confirms the structure and regiochemistry of the cycloaddition. 相似文献
74.
A series of novel N‐methyl spiropyrrolidines have been synthesized in good yield by the cycloaddition reaction of azomethine ylides generated by a decarboxylative route from sarcosine and paraformaldehyde with conformationally locked s‐trans enone functionality present in the (E)‐3‐arylidene‐4‐chromanone as dipolarophiles. The structure of the title compound was established by spectroscopic techniques. 相似文献
75.
Mohammad Javad Taghizadeh Hamid ArvinnezhadSaadi Samadi Khosrow Jadidi Abdollah JavidanBehrouz Notash 《Tetrahedron letters》2012,53(38):5148-5150
An efficient, one-pot, three-component procedure for the synthesis of a small library of new chiral spirooxindolopyrrolizidines with high regio-, diastereo-, and enantioselectivity, from the 1,3-dipolar cycloaddition of azomethine ylides and optically active cinnamoyl oxazolidinone is described. The process occurs at room temperature in aqueous ethanol as a green solvent and in the absence of any Lewis acids. The oxazolidinone chiral auxiliary is removed in a non-destructive manner. The reaction mechanism is discussed on the basis of the assignment of the absolute configuration of the cycloadducts, and on theoretical calculations. 相似文献
76.
A new zinc coordination polymer, [Zn(L)(bpp)·H2O]n, was synthesized using 5-dimethylamino-isophthalic acid (H2L) and 1,3-bis(4-pyridyl)propane (bpp) as organic linkers. In the complex, adjacent Zn2+ ions are linked by L2? anions to form a one-dimensional (1D) [ZnL]n chain. Then bpp ligands expand the 1D chains into a corrugated two-dimensional (2D) layer network by linking neighboring Zn2+ ions. These adjacent layers are further stacked together by direct C?H···π supramolecular interactions, generating a three-dimensional (3D) supramolecular structure. From the viewpoint of topology, the 2D network can be rationalized to a uninodal four-connected non-interpenetrated sql/Shubnikov tetragonal plane net with {44.62} topology. Moreover, the solid state properties such as thermogravimetric analysis and luminescence were also investigated. 相似文献
77.
Jérôme LalotTony Tite Anne WadouachiDenis Postel Albert Nguyen Van Nhien 《Tetrahedron》2011,67(33):6006-6017
C-branched-chain sugars and nucleosides were obtained by organocatalysis from ulose derivatives. After a reduction step, the corresponding 1,3-diol was derivatized into 3′-spiro-sulfamidates and unexpected sulfates by treatment with a Burgess reagent. Deprotection of the Boc-derivatives was carried out while preserving the cyclic sulfate. An example of ring opening of the cyclic sulfate derivative with sodium azide leading to the corresponding 3′-C-azidoalkyl branched-chain nucleosides is given. 相似文献
78.
Ankita RaiLal Dhar S. Yadav 《Tetrahedron letters》2011,52(30):3933-3936
The first one-pot three-component coupling reaction of O,O-diethyl hydrogen phosphorodithioate, aldehydes, and aldimines affording 1,2,4-trisubstituted 1,3-thiazetidines is reported. The product is obtained in moderate to high yields (45-94%) and has excellent diastereoselectivity (90-96%) in favour of the cis isomer. Shorter reaction times, ambient temperature, operational simplicity, and high yields are the salient features of the present procedure. 相似文献
79.
An efficient protocol for the one-pot preparation of alkyl 3-aryl-5-methylisoxazole-4-carboxylates from aryl aldehydes is described. This method is readily amenable to the large scale preparation of isoxazoles as well as the parallel synthesis of isoxazole libraries. 相似文献
80.
Mudumala Veeranarayana ReddySomeshwar D. Dindulkar Yeon Tae Jeong 《Tetrahedron letters》2011,52(37):4764-4767
α-Aminophosphonates were synthesized in a simple and efficient method from the three-component condensation reaction of 5-amino 2,2-difluoro-1,3-benzodioxole, aromatic aldehydes, and diethyl phosphite by silica-supported boron trifluoride (BF3·SiO2) in ionic liquid ([bmim][HCl]) under solvent-free conditions at room temperature in good to excellent yields and short reaction times. The catalyst can be recovered and reused for several times without any significant loss of activity. It was observed that a homogeneous reaction medium proved beneficial for the yield of the reaction. 相似文献