Experiments directed towards the synthesis of anthracyclinones. III. β-Formylation of hydroxyanthraquinones by the Claisen rearrangement

1977 ◽  
Vol 30 (8) ◽  
pp. 1743 ◽  
Author(s):  
JL Roberts ◽  
PS Rutledge
Keyword(s):  
Claisen Rearrangement ◽  
Allyl Ether ◽  
Olefinic Bond ◽  
Thermally Induced

β-Formylation of an α-hydroxyanthraquinone is shown to be possible by way of thermally induced rearrangement of the allyl ether, migration of the olefinic bond, and ozonolysis.

scholarly journals Ring-closing-metathesis-based synthesis of annellated coumarins from 8-allylcoumarins

2018 ◽  
Vol 14 ◽  
pp. 2991-2998 ◽  
Author(s):  
Christiane Schultze ◽  
Bernd Schmidt
Keyword(s):  
Double Bond ◽  
Olefin Metathesis ◽  
Claisen Rearrangement ◽  
Allylic Oxidation ◽  
Allyl Ether ◽  
Ring Closing Metathesis ◽  
Wittig Olefination

8-Allylcoumarins are conveniently accessible through a microwave-promoted tandem Claisen rearrangement/Wittig olefination/cyclization sequence. They serve as a versatile platform for the annellation of five- to seven-membered rings using ring-closing olefin metathesis (RCM). Furano-, pyrano-, oxepino- and azepinocoumarins were synthesized from the same set of precursors using Ru-catalyzed double bond isomerizations and RCM in a defined order. One class of products, pyrano[2,3-f]chromene-2,8-diones, were inaccessible through direct RCM of an acrylate, but became available from the analogous allyl ether via an assisted tandem catalytic RCM/allylic oxidation sequence.

The carbon analogue of the claisen rearrangement of phenyl allyl ether

Tetrahedron ◽  
1966 ◽  
Vol 22 (2) ◽  
pp. 385-391 ◽  
Author(s):  
W. von E Doering ◽  
R.A. Bragole
Keyword(s):  
Claisen Rearrangement ◽  
Allyl Ether

Wilzbach tritiation studies. I. Isotope distribution in tritium-labelled anthranilic acid, isopropanol and phenyl allyl ether

1965 ◽  
Vol 18 (3) ◽  
pp. 297 ◽  
Author(s):  
JL Garnett ◽  
SW Law ◽  
AR Till
Keyword(s):  
Anthranilic Acid ◽  
Claisen Rearrangement ◽  
Total Activity ◽  
Hydroxyl Group ◽  
Allyl Ether ◽  
Radical Mechanism ◽  
Isotope Distribution ◽  
Hydrogen Position ◽  
Radiation Induced ◽  
Distribution Studies

Isotope distribution studies with anthranilic acid labelled by the Wilzbach method indicate that positions 3 and 5 have respectively 49.8% and 27.4% of the total activity, tritium incorporation thus tending to be highest at the most electronegative positions. In isopropanol the hydroxyl group contains approximately three times as much isotope as at any other hydrogen position, while tritiation of the secondary C-H is slightly more efficient than the primary C-H. In the tritiation of phenyl ally1 ether, the predominant process is polymerization after reasonable exposure time, little radiation-induced Claisen rearrangement or saturation of the double bond being observed. A free radical mechanism has been proposed to account for the above distributions which have also been compared with results obtained by catalytic exchange. From these model compounds the relative preparative applicability of the Wilzbach and catalytic techniques has been discussed.

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