Rearrangements in the Diterpenoid Series. I. The Solvolysis of Methyl 15β-tosyloxy-13-isopropyl-17-noratis-13-en-18-oate

1973 ◽  
Vol 51 (1) ◽  
pp. 77-86 ◽  
Author(s):  
William A. Ayer ◽  
Pandurang D. Deshpande
Keyword(s):  
Diels Alder ◽  
Vinyl Ketone ◽  
Methyl Vinyl Ketone ◽  
Unsaturated Ketone ◽  
Methyl Vinyl ◽  
Levopimaric Acid ◽  
Alder Adduct

The synthesis of methyl 15β-hydroxy-13-isopropyl-17-noratis-13-en-18-oate (14b) is described. Compound 14b was prepared from the ketone 12b, in turn derived from the Diels–Alder adduct formed between levopimaric acid (7) and α-acetoxyacrylonitrile. Solvolysis of the tosylate of 14b proceeds predominantly with rearrangement and elimination to give methyl 16-isopropylidene-7,17-secoacon-8(15)-en-18-oate (16a). This rearrangement serves as a model for the proposed biosynthetic transformation of atisine-type alkaloids into alkaloids of the aconitine series. The degradation of 16a into the unsaturated ketone 19, which contains the 19 carbons of the aconane skeleton, is described. The Diels–Alder addition of methyl vinyl ketone to levopimaric acid is reported and the adduct is shown to possess structure 8.

scholarly journals An exceptional 5-endo–trig reversal; a convergent synthesis of daunomycinone

1983 ◽  
Vol 61 (3) ◽  
pp. 637-639 ◽  
Author(s):  
B. A. Keay ◽  
R. Rodrigo
Keyword(s):  
Diels Alder ◽  
Vinyl Ketone ◽  
Methyl Vinyl Ketone ◽  
Convergent Synthesis ◽  
Methyl Vinyl ◽  
Alder Adduct

A convergent AB + CD route to daunomycinone (1) is described. The AB segment is synthesized from the Diels–Alder adduct (3) of an isobenzofuran and methyl vinyl ketone by means of an unusual 5-endo–trig cleavage (3 → 4). The CD half (9) is combined with the AB by the Kraus annelation technique to provide a 9-deoxy daunomycinone derivative (12a) which is subsequently oxygenated.

scholarly journals The Diels-Alder reaction of 3-acetoxy-1-vinylcyclohexene with methyl vinyl ketone.

1989 ◽  
Vol 37 (9) ◽  
pp. 2307-2309 ◽  
Author(s):  
Takeshi KAWAMATA ◽  
Kenzo HARIMAYA ◽  
Yoichi IITAKA ◽  
Seiichi INAYAMA
Keyword(s):  
Alder Reaction ◽  
Diels Alder ◽  
Vinyl Ketone ◽  
Methyl Vinyl Ketone ◽  
Methyl Vinyl ◽  
Diels Alder Reaction

Diels–Alder cycloadditions of vinyl- and propenyl-allene to methyl vinyl ketone

1968 ◽  
Vol 0 (19) ◽  
pp. 1141-1142 ◽  
Author(s):  
M. Bertrand ◽  
J. Grimaldi ◽  
B. Waegell
Keyword(s):  
Diels Alder ◽  
Vinyl Ketone ◽  
Methyl Vinyl Ketone ◽  
Methyl Vinyl

scholarly journals Attempted Diels-Alder Reactions on Vindoline Derivatives

2017 ◽  
Vol 61 (4) ◽  
pp. 258 ◽  
Author(s):  
Szabolcs Mayer ◽  
Péter Keglevich ◽  
Péter Ábrányi-Balogh ◽  
Áron Szigetvári ◽  
Miklós Dékány ◽  
...  
Keyword(s):  
Alder Reaction ◽  
Diels Alder ◽  
Vinyl Ketone ◽  
Methyl Vinyl Ketone ◽  
Methyl Vinyl ◽  
Diels Alder Reaction ◽  
Quinone Derivative

The Diels-Alder reaction of vindoline and methyl vinyl ketone resulted in a Friedel-Crafts reaction product. In the reaction between the ortho-quinone derivative of vindoline and N-phenylmaleimide, two anomalous products were obtained, a vindoline dimer, and a condensed vindoline derivative.

CROSS-LINKING OF COPOLYMERS FROM METHYL VINYL KETONE AND n-BUTYL ACRYLATE

1956 ◽  
Vol 34 (3) ◽  
pp. 387-405 ◽  
Author(s):  
W. Cooper ◽  
E. Catterall
Keyword(s):  
Zinc Oxide ◽  
Butyl Acrylate ◽  
Oxide System ◽  
Vinyl Ketone ◽  
Methyl Vinyl Ketone ◽  
Cross Linking ◽  
Unsaturated Ketone ◽  
Methyl Vinyl ◽  
Or Groups ◽  
Cross Links

Copolymers of n-butyl acrylate and methyl vinyl ketone can be cross-linked by a combination of sulphur and zinc oxide; the reaction is associated with the methyl vinyl ketone units in the polymer chain. From studies on the copolymers and model compounds, it is suggested that adjacent pairs or groups of methyl vinyl ketone units in the polymer cyclize to give αβ unsaturated ketone groups. These contain reactive hydrogen which is attacked by sulphur; disulphide or zinc mercaptide cross-links are then formed. Water is produced in the cyclization reaction and hydrolyzes some of the ester groups; additional cross-links are thus formed by reaction of the acid groups with zinc oxide. The ease of cyclization and, therefore, the extent of cross-linking is dependent on the method of preparing the copolymers, emulsion copolymers being much more reactive than those prepared in solution. A comparison has been made between the sulphur + zinc oxide system and other cross-linking agents which may be used for polyacrylates.

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