Synthesis of 3,4-bis[(methoxycarbonyl)methyl]thiophene and bis-, ter- and pentathiophenes with alternating 3,4-bis[(methoxycarbonyl)methyl]-substituted rings
摘要:
The synthesis of 3,4-bis[(methoxycarbonyl)methyl]thiophene and bis-, ter- and pentathiophenes, with alternating 3,4-bis(methoxycarbonyl)methyl-substituted rings, is reported, These new thiophene derivatives are possible precursors for the preparation of new conducting polymers useful as materials for electronics. (C) 1998 Elsevier Science Ltd. All rights reserved.
[EN] ELECTROCHEMICALLY-CLEAVABLE LINKERS<br/>[FR] LIEURS CLIVABLES PAR VOIE ÉLECTROCHIMIQUE
申请人:MICROSOFT TECHNOLOGY LICENSING LLC
公开号:WO2021158412A1
公开(公告)日:2021-08-12
This disclosure provides electrochemically-cleavable linkers with cleavage potentials that are less than the redox potential of the solvent in which the linkers are used. In some applications, the solvent may be water or an aqueous buffer solution. The linkers may be used to link a nucleotide to a bound group. The linkers include a cleavable group which may be one of a methoxybenzyl alcohol, an ester, a propargyl thioether, or a trichloroethyl ether. The linkers may be cleaved in solvent by generating an electrode potential that is less than the redox potential of the solvent. In some implementations, an electrode array may be used to generate localized electrode potentials which selectively cleave linkers bound to the activated electrode. Uses for the linkers include attachment of blocking groups to nucleotides in enzymatic oligonucleotide synthesis.
containing functional groups such as ester, ketone, nitrile, amine, alcohol, sulfide, etc. can be used for the present ruthenium catalysis. The most significant advantage of this protocol is that the cycloaddition of unsymmetrical 1,6-diynes with one internal alkyne moiety regioselectively gave rise to meta-substituted products with excellent regioselectivity. Completely intramolecular alkyne cyclotrimerization
to afford bicyclic pyridines. Careful screening of nitrile components revealed that a C[triple chemical bond]C triple bond or heteroatom substituents, such as methoxy and methylthio groups, proved to act as the coordinating groups, whereas C==C or C==O doublebonds and amino groups failed to promote cycloaddition. This suggests that coordinating groups with multiple pi-bonds or lone pairs are essential
Preparation of Structurally and Electronically Diverse N → B-Ladder Boranes by [2 + 2 + 2] Cycloaddition
作者:Jonas D. W. Schepper、Andreas Orthaber、Frank Pammer
DOI:10.1021/acs.joc.1c01402
日期:2021.11.5
We report the synthesis of a series of eight N → B-ladder boranes through cobalt-mediated cyclotrimerization of (2-cyanophenyl)-dimesitylborane with different dialkynes. The resulting tetracoordinate boranes show variable electrochemical and optical properties depending on the substitution pattern in the backbone of the coordinating pyridine-derivatives. While boranes containing alkyl-substituted pyridines
我们报告了通过钴介导的(2-氰基苯基)-二甲基硼烷与不同二炔的环三聚反应合成了一系列八个 N → B-梯级硼烷。所得四配位硼烷根据配位吡啶衍生物骨架中的取代模式显示出不同的电化学和光学性质。虽然含有烷基取代的吡啶的硼烷比已知的母体化合物显示出较低的电子亲和力,但具有 π 扩展吡啶衍生物的硼烷在受体取代的三芳基硼烷范围内显示出更高的电子亲和力。与未取代吡啶配位的 N → B-梯形硼烷相比,所有衍生物都显示出更大的斯托克斯位移 (8790–6920 cm –1 )。
Cp*RuCl-Catalyzed [2 + 2 + 2] Cycloadditions of α,ω-Diynes with Electron-Deficient Carbon−Heteroatom Multiple Bonds Leading to Heterocycles
In the presence of a catalytic amount of Cp*RuCl(cod), 1,6-diynes were allowed to react chemo- and regioselectively with electron-deficient nitriles and heterocumulenes at 60−90 °C to afford heterocyclic compounds. The mechanism of the ruthenium-catalyzed regioselective formations of bicyclic pyridines and pyridones were analyzed on the basis of density functional calculations. Cyclocotrimerizations
在催化量的 Cp*RuCl(cod) 存在下,1,6-二炔可以在 60-90 °C 下与缺电子腈和杂枯烯进行化学和区域选择性反应,得到杂环化合物。在密度泛函计算的基础上分析了钌催化的双环吡啶和吡啶酮区域选择性形成的机制。丙炔酸乙酯与氰基甲酸乙酯或异氰酸丙酯的环三聚反应产生四种可能的吡啶或吡啶酮区域异构体中的两种。