Chemoselective Homologation–Deoxygenation Strategy Enabling the Direct Conversion of Carbonyls into (<i>n+1</i>)-Halomethyl-Alkanes
作者:Margherita Miele、Andrea Citarella、Thierry Langer、Ernst Urban、Martin Zehl、Wolfgang Holzer、Laura Ielo、Vittorio Pace
DOI:10.1021/acs.orglett.0c02831
日期:2020.10.2
The sequential installation of a carbenoid and a hydride into a carbonyl, furnishing halomethyl alkyl derivatives, is reported. Despite the employment of carbenoids as nucleophiles in reactions with carbon-centered electrophiles, sp3-type alkyl halides remain elusive materials for selective one-carbon homologations. Our tactic levers on using carbonyls as starting materials and enables uniformly high
A novel regio- and stereoselective reductive coupling of vinyl azaarenes and alkynes has been developed to access functionalized azaarene compounds bearing stereodefined tri-substituted alkenes via photoredox cobalt dualcatalysis. Simple organic base together with alcohol has been applied as the hydrogen sources instead of commonly used Hantzsch esters in this coupling reaction.
Regio- and Stereoselective Reductive Coupling of Alkynes and Crotononitrile
作者:Kun Cui、Yan-Lin Li、Gongqiang Li、Ji-Bao Xia
DOI:10.1021/jacs.2c10021
日期:2022.12.21
bearing a stereodefinedtrisubstitutedalkene have been easily synthesized with good to excellent regio- (up to >20:1 rr), stereo- (>20:1 E/Z), and enantioselectivity (up to 98% ee) control under mild conditions. The corresponding nitrile products were smoothly converted into various chiral building blocks. Remarkably, a simple organic base together with water have been utilized as hydrogen sources in this
通过可见光有机光氧化还原钴双催化开发了炔烃和巴豆腈的新区域选择性和立体选择性还原偶联。多种带有立构定义的三取代烯烃的对映体富集的同烯丙基腈很容易合成,具有良好到极好的区域-(高达 >20:1 rr)、立体-(>20:1 E / Z)和对映选择性(高达 98% ee) 在温和条件下控制。相应的腈产物顺利转化为各种手性结构单元。值得注意的是,在这种光诱导还原反应中,一种简单的有机碱与水一起被用作氢源。
Thallium in organic synthesis. XXXIV. Oxidations of acetylenes with thallium(III) nitrate (TTN)
作者:Alexander. McKillop、Otto H. Oldenziel、Brian P. Swann、Edward C. Taylor、Roger L. Robey
DOI:10.1021/ja00785a047
日期:1973.2
Copper-Catalyzed Three-Component Borylstannylation of Alkynes
作者:Yuki Takemoto、Hiroto Yoshida、Ken Takaki
DOI:10.1002/chem.201202435
日期:2012.11.12
AbstractRegio‐ and stereoselective installation of boryl and stannyl moieties into a carbon–carbon triple bond of various alkynes has been achieved based on a three‐component coupling reaction by using a diboron and a tin alkoxide with the aid of a copper(II) acetate–tricyclohexylphosphine complex, giving diverse vic‐borylstannylalkenes in a straightforward manner. Carbon–tin and carbon–boron bonds of the resulting borylstannylation product are successively transformed into carbon–carbon bonds by a Migita–Kosugi–Stille and a Suzuki–Miyaura coupling, leading to the formation of (Z)‐tamoxifen with anti‐breast cancer activity.