Synthesis of Naphthalenyl Triflates via the Cationic Annulation of Benzodiynes with Triflic Acid
摘要:
A highly efficient and regioselective annulation of benzodiynes promoted by triflic acid has been developed. This protocol provides a step and atom-economic access to a series of naphthalenyl triflates. Furthermore, direct synthetic applications of this reaction are also elaborated through cross-coupling reactions to generate synthetically useful multisubstituted naphthalenes.
Rerouting Radical Cascades: Intercepting the Homoallyl Ring Expansion in Enyne Cyclizations via C–S Scission
作者:Sayantan Mondal、Brian Gold、Rana K. Mohamed、Hoa Phan、Igor V. Alabugin
DOI:10.1021/jo5012043
日期:2014.8.15
to 6-endo-trig selectivity in the radicalcyclization of aromatic enynes was probed via the combination of experimental and computational methods. This transformation occurs by kinetic self-sorting of the mixture of four equilibrating radicalsvia 5-exo-trig cyclization, followed by homoallyl (3-exo-trig/fragmentation) ring expansion to afford the benzylic radical necessary for the final aromatizing
Cationic Au(I)-Catalyzed Cycloisomerization of Aromatic Enynes for the Synthesis of Substituted Naphthalenes
作者:Takanori Shibata、Yasunori Ueno、Kazumasa Kanda
DOI:10.1055/s-2006-926261
日期:——
A cationic Au(I) complex catalyzed the cycloisomerization of aromaticenynes that possess a substituent on their alkyne terminus. Cyclization of the 6-endo-dig type proceeded dominantly to give 1,3-di- and 1,2,3-trisubstituted naphthalenes.
Cyclization of (2-Alkenylphenyl)carbonyl Compounds to Polycyclic Arenes Catalyzed by Copper(II) Trifluoromethanesulfonate or Trifluoromethanesulfuric Acid
作者:Wei-Min Liu、Ya Lin Tnay、Kian Ping Gan、Zhen-Hong Liu、Wan Huei Tyan、Koichi Narasaka
DOI:10.1002/hlca.201200396
日期:2012.10
Various polycyclicarenes, such as naphthalenes, tetrahydroantharacenes, tetrahydrotetracenes, dihydropentacenes, and dihydropentaphenes are prepared from 2‐alkenylphenyl ketones and aldehydes by the catalytic use of copper(II) trifluoromethanesulfonate (Cu(OTf)2) or trifluoromethanesulfuricacid (TfOH).
Alkenes as Alkyne Equivalents in Radical Cascades Terminated by Fragmentations: Overcoming Stereoelectronic Restrictions on Ring Expansions for the Preparation of Expanded Polyaromatics
作者:Rana K. Mohamed、Sayantan Mondal、Brian Gold、Christopher J. Evoniuk、Tanmay Banerjee、Kenneth Hanson、Igor V. Alabugin
DOI:10.1021/jacs.5b02373
日期:2015.5.20
Chemoselective interaction of aromatic enynes with Bu3Sn radicals can be harnessed for selective cascade transformations, yielding either Sn-substituted naphthalenes or Sn-indenes. Depending on the substitution at the alkene terminus, the initial regioselective 5-exo-trig cyclizations can be intercepted at the 5-exo stage via either hydrogen atom abstraction or C-S bond scission or allowed to proceed
Gold(I)-Catalyzed Cycloisomerizations and Alkoxycyclizations of<i>ortho</i>-(Alkynyl)styrenes
作者:Ana M. Sanjuán、Muhammad A. Rashid、Patricia García-García、Alberto Martínez-Cuezva、Manuel A. Fernández-Rodríguez、Félix Rodríguez、Roberto Sanz
DOI:10.1002/chem.201405789
日期:2015.2.9
Indenes and related polycyclic structures have been efficiently synthesized by gold(I)‐catalyzed cycloisomerizations of appropriate ortho‐(alkynyl)styrenes. Disubstitution at the terminal position of the olefin was demonstrated to be essential to obtain products originating from a formal 5‐endo‐dig cyclization. Interestingly, a complete switch in the selectivity of the cyclization of o‐(alkynyl)‐α‐methylstyrenes