Cyclisation of acetylenic ethoxylactams 1b-12b leads to bridgehead nitrogen bicyclic ketones in excellent yields. The reaction is weakly acid-catalysed and proceeds at ambient temperature. The observed regioselectivity effect is discussed in terms of stability of exo vs endo vinylcations and ring strain effects. The high yield conversion of N-(5-hexynyl)-ethoxy lactams 7b and 8b in the 5/8 and 6/8
Gold(I)-Catalyzed Hydroaminaloxylation and Petasis–Ferrier Rearrangement Cascade of Aminaloalkynes
作者:Amol B. Gade、Nitin T. Patil
DOI:10.1021/acs.orglett.6b00585
日期:2016.4.15
An efficient method has been developed to generate a diverse array of indolizidines and quinolizidines from readily available aminaloalkynes via a gold(I)-catalyzed hydroaminaloxylation and Petasis–Ferrier rearrangement cascade. The method enabled a formal synthesis of (±)-antofine.
A novel regio‐ and diastereoselective iron‐catalyzed intermolecular oxyazidation of enamidesusing various azidobenziodoxolone (ABX) derivatives is presented. A variety of α‐N3 amino derivatives and of α‐N3 piperidines were synthesized in good yields and under mild reaction conditions. The reaction involves a radical process using cheap FeCl2 as the initiator.
Sonogashira/N-acyliminium ion aromatic π-cyclisation processes: access to tetra- and pentacyclic lactams
作者:Ronald Grigg、Visuvanathar Sridharan、David A. Sykes
DOI:10.1016/j.tet.2008.06.044
日期:2008.9
Application of the Sonogashira reaction of N-alkynylimides with 2-iodophenol or 2-iodo-N-tosylaniline affords 2-(N-alkylimino)-benzofurans and indoles in good yield. Selective partial reduction of the latter followed by treatment with TsOH generates N-acyliminium ions, which cyclise to afford tetra- and pentacyclic lactams in good yield. The latter are reduced to the analogous cyclic amines by BH3. (C) 2008 Elsevier Ltd. All rights reserved.
SCHOEMAKER H. E.; BOER-TERPSTRA T.; DIJKINK J.; SPECKAMP W. N., TETRAHEDRON, 1980, 36, NO 1, 143-148
作者:SCHOEMAKER H. E.、 BOER-TERPSTRA T.、 DIJKINK J.、 SPECKAMP W. N.