Dual Gold‐Catalyzed Cycloaromatization of Unconjugated (
<i>E</i>
)‐Enediynes
作者:Farzad Zamani、Rasool Babaahmadi、Brian F. Yates、Michael G. Gardiner、Alireza Ariafard、Stephen G. Pyne、Christopher J. T. Hyland
DOI:10.1002/anie.201810794
日期:2019.2.11
A synthesis of unconjugated (E)‐enediynes from allenyl amino alcohols is reported and their gold‐catalyzed cascade cycloaromatization to a broad range of enantioenriched substituted isoindolinones has been developed. Experimental and computational studies support the reaction proceeding via a dual‐gold σ,π‐activation mode, involving a key gold‐vinylidene‐ and allenyl‐gold‐containing intermediate.
Oxazolidinones and 2,5-Dihydrofurans via Zinc-Catalyzed Regioselective Allenylation Reactions of <scp>l</scp>-α-Amino Aldehydes
作者:Farzad Zamani、Stephen G. Pyne、Christopher J. T. Hyland
DOI:10.1021/acs.joc.7b00969
日期:2017.7.7
The simultaneous control of diastereoselectivity and regioselectivity in Zn-catalyzed allenylation reactions of N-protected L-alpha-amino aldehydes is reported. A reversal in diastereoselectivity could be realized by variation of the alpha-amino aldehyde protecting groups. A range of 1-allenyl-2-amino alcohols were obtained with excellent regioselectivity and converted to oxazolidinones and dihydrofurans. Many of which could be isolated as single diastereoisomers and without significant erosion of ee, making this a practical catalytic synthesis of highly functionalized heterocycles.
Scope and limitations of the alkylidene carbene 1,5-CH insertion reactions of α-amino acid-derived substrates
作者:Renameditswe Mapitse、Christopher J Hayes
DOI:10.1016/s0040-4039(02)00585-3
日期:2002.5
A range of alpha-amino acid-derived cyclisation precursors were synthesised from suitably protected alpha-amino esters, via a Dibal-H/Wittig/catalytic hydrogenation strategy and each of these was subjected to alkylidene carbene-forming conditions (lithio(trimethylsilyl)diazomethane, THF). The cyclisations proceeded in poor to good yield, with the best cyclisations occurring to produce spirocyclic products. (C) 2002 Published by Elsevier Science Ltd.
Hormuth, Stephan; Reissig, Hans-Ulrich; Dorsch, Dieter, Liebigs Annalen der Chemie, 1994, # 2, p. 121 - 128