Regioselective Synthesis of C-3-Functionalized Quinolines via Hetero-Diels–Alder Cycloaddition of Azadienes with Terminal Alkynes
作者:Rakesh K. Saunthwal、Monika Patel、Akhilesh K. Verma
DOI:10.1021/acs.joc.6b01186
日期:2016.8.5
C-3-functionalized quinolines from azadienes (in situ generated from 2-aminobenzyl alcohol) and terminal alkynes through [4 + 2] cycloaddition has been developed. An unprecedented reaction of 2-aminobenzyl alcohol with 1,3- and 1,4-diethynylbenzene provided the C-3 tolylquinolines via [4 + 2] HDA and oxidative decarboxylation. The −NH2 group directed mechanistic approach was well supported by the control experiments
Functionalization of Alkynes Catalyzed byt-Bu-P4 Base
作者:Tatsushi Imahori、Chieko Hori、Yoshinori Kondo
DOI:10.1002/adsc.200404076
日期:2004.8
The addition of O- and N-nucleophiles to alkynescatalyzed by a phosphazene base, t-Bu-P4 base, was investigated. Alkynes were easily transformed to enol ethers and enamines in DMSO by the addition of nucleophiles. When phenylacetylene was reacted with diisopropylamine, a unique head-to-head dimerization of phenylacetylene was observed to give the enyne derivative. Terminal proton of phenylacetylene
In the presence of catalytic amounts of cesium hydroxide (CsOH·H2O), alcohols, substituted anilines and heterocyclic amines undergo an addition in NMP to phenylacetylene leading to functionalized enol ethers and enamines. Anilines add to styrene (90–120°C, 12–14 h) leading to N-substituted anilines in satisfactory yields.