125454-79-7Relevant articles and documents
Sequential Carbon-Carbon/Carbon-Selenium Bond Formation Mediated by Iron(III) Chloride and Diorganyl Diselenides: Synthesis and Reactivity of 2-Organoselenyl-Naphthalenes
Recchi, Ana M. S.,Back, Davi F.,Zeni, Gilson
, p. 2713 - 2723 (2017)
In this paper, we report an intramolecular cyclization of benzylic-substituted propargyl alcohols promoted by iron(III) chloride and diorganyl diselenides to give 2-organoselenyl-naphthalenes via a sequential carbon-carbon/carbon-selenium bond formation. The present reaction tolerated a wide range of substituents in both propargyl alcohols and diorganyl diselenides to give the desired 2-organoselenyl-naphthalenes in good yields with high selectivity. In addition, O-acyl protected propargyl alcohol and propargyl bromide were also subjected to this protocol giving the corresponding 2-organoselenyl-naphthalenes. We found that dichalcogenide species affected the formation of cyclized products, whereas diorganyl diselenides gave high yields, moderate yields were obtained with diorganyl disulfides, and no product formation was found with diorganyl ditellurides. The key transformations could be attributed to the carbon-carbon triple bond activation of benzylic-substituted propargyl alcohols by a seleniranium ion, antiattack of the electron cloud from the aromatic ring at the activated triple bond, and cyclization via an exclusive 6-endo-dig process. We also found that the corresponding 2-organoselenyl-naphthalenes are suitable substrates to the selenium-lithium exchange reactions followed by trapping with aldehydes affording the corresponding secondary alcohols.
Scalable, Stereocontrolled Formal Syntheses of (+)-Isoschizandrin and (+)-Steganone: Development and Applications of Palladium(II)-Catalyzed Atroposelective C?H Alkynylation
Liao, Gang,Yao, Qi-Jun,Zhang, Zhuo-Zhuo,Wu, Yong-Jie,Huang, Dan-Ying,Shi, Bing-Feng
supporting information, p. 3661 - 3665 (2018/03/05)
Dibenzocyclooctadiene lignans are an interesting class of molecules because of their unique structure based on an axially chiral biaryl moiety as well as their significant biological activity. Herein, we describe the development of a palladium-catalyzed atroposelective C?H alkynylation and its application in gram-scale, stereocontrolled formal syntheses of (+)-isoschizandrin and (+)-steganone. tert-Leucine was identified as an efficient, catalytic transient chiral auxiliary. A wide range of enantiomerically enriched biaryl compounds were prepared by this approach in good yields (up to 99 %) with excellent enantioselectivity (up to >99 % ee).
Gold-catalyzed 6-exo-dig cycloisomerization: A versatile approach to functionalized phenanthrenes
Shu, Chao,Li, Long,Chen, Cheng-Bin,Shen, Hong-Cheng,Ye, Long-Wu
supporting information, p. 1525 - 1529 (2014/06/09)
A novel gold-catalyzed 6-exo-dig cycloisomerization of o-propargylbiaryls has been developed that provides ready access to functionalized phenanthrenes in largely good to excellent yields. Notable features of this method are readily available starting materials, mild reaction conditions, and broad substrate scope. Golden cat: A novel gold-catalyzed 6-exo-dig cycloisomerization of o-propargylbiaryls has been developed that provides ready access to functionalized phenanthrenes in largely good to excellent yields. Notable features of this method are readily available starting materials, mild reaction conditions, and broad substrate scope.
