Aza-Conjugate Addition Methodology for the Synthesis of N-Hydroxy-isoindolin-1-ones
摘要:
Aryl-aldehydes containing ortho-substituted propiolate fragments react with hydroxylamine to afford carbinolamine intermediates that undergo intramolecular aza-conjugate addition reactions to afford N-hydroxy-2.3-dihydro-isoindolin-l-ones that can be reduced to their corresponding isoindolin-l-ones and isoindoles.
Aza-Conjugate Addition Methodology for the Synthesis of N-Hydroxy-isoindolin-1-ones
摘要:
Aryl-aldehydes containing ortho-substituted propiolate fragments react with hydroxylamine to afford carbinolamine intermediates that undergo intramolecular aza-conjugate addition reactions to afford N-hydroxy-2.3-dihydro-isoindolin-l-ones that can be reduced to their corresponding isoindolin-l-ones and isoindoles.
Silver-Catalyzed Reaction of Enynals with Alkenes: A Tandem 1,3-Dipolar Cycloaddition/Cyclopropanation
作者:Renxiao Liang、Tongmei Ma、Shifa Zhu
DOI:10.1021/ol5017299
日期:2014.9.5
silver-catalyzed reaction of enynals with alkenes to synthesize a series of polycyclic compounds has been developed. The reaction occurred smoothly using enynals with electron-deficient alkynes or terminal alkynes as substrates. The reaction was proposed to proceed through a tandem 1,3-dipolar cycloaddition/cyclopropanation process. The preliminary investigations of the asymmetric catalytic version revealed that
Salt-Free Strategy for the Insertion of CO<sub>2</sub>
into C−H Bonds: Catalytic Hydroxymethylation of Alkynes
作者:Timo Wendling、Eugen Risto、Thilo Krause、Lukas J. Gooßen
DOI:10.1002/chem.201800526
日期:2018.4.20
A copper(I) catalyst enables the insertion of carbondioxide into alkyne C−H bonds by using a suitable organic base with which hydrogenation of the resulting carboxylate salt with regeneration of the base becomes thermodynamically feasible. In the presence of catalytic copper(I) chloride/4,7‐diphenyl‐1,10‐phenanthroline, polymer‐bound triphenylphosphine, and 2,2,6,6‐tetramethylpiperidine as the base
铜(I)催化剂可通过使用合适的有机碱将二氧化碳插入炔烃的C H键中,利用该有机碱在热力学上可实现对羧酸盐的氢化以及碱的再生。在催化氯化铜(I)/ 4,7-二苯基-1,10-菲咯啉,聚合物结合的三苯基膦和2,2,6,6-四甲基哌啶为碱的情况下,末端炔烃在15 bar CO下进行羧化反应2,室温。过滤后,可以在铑/钼催化剂下将炔羧酸铵氢化为伯醇和水,以再生胺碱。这证明了无盐整体工艺的可行性,在该工艺中,二氧化碳可充当CH功能中C1的基石。
Catalytic [1,3] O-to-C Rearrangement: Rapid Access to Bridged Bicyclic Systems
A catalytic [1,3] O‐to‐C rearrangement from enyne‐ethers was developed for the rapid synthesis of diverse bridged bicyclic systems. In this reaction, a vinyl oxonium intermediate, generated in situ from enyne‐ether, was the precursor for the [1,3] O‐to‐C rearrangement. This versatile protocol represents the first example of catalytic [1,3] O‐to‐C rearrangement based on ring‐expansion strategy, enabling
Cascade One-Pot Synthesis of Indanone-Fused Cyclopentanes from the Reaction of Donor-Acceptor Cyclopropanes and Enynals <i>via</i>
a Sequential Hydrolysis/Knoevenagel Condensation/[3+2] Cycloaddition
作者:Jiantao Zhang、Huanfeng Jiang、Shifa Zhu
DOI:10.1002/adsc.201700345
日期:2017.9.4
to construct indanone‐fused cyclopentanes via a sequential hydrolysis/Knoevenagelcondensation/[3+2] cycloaddition is reported. The desired indanone‐fused cyclopentanes were obtained in good yields. This method features mild reaction conditions and broad substrate scope, which render it very appealing to chemists for the synthesis of complex molecules containing an indanone‐fused cyclopentane moiety
An efficient route to highly strained cyclobutenes: indium-catalyzed reactions of enynals with alkynes
作者:Renxiao Liang、Huanfeng Jiang、Shifa Zhu
DOI:10.1039/c4cc08506j
日期:——
synthesize the highly strained cyclobutene was developed. The reaction was believed to proceed through a formal indium-catalyzed [2+2] cycloaddition between electron-deficient enynals and various alkynes.