Unsaturated Ketoesters Research Articles

ChemInform Abstract: SYNTHESIS OF 12α AND 12β‐CARBOXYESTRADIOL DERIVATIVES VIA THE THERMAL ELIMINATION OF β‐KETOSULFOXIDE

AbstractBei der Thermolyse des Methylsulfinylcarbonsäureesters (I) entsteht ein Vinylketon, das durch Michaelkondensation mit dem Methylcyclopentandion (II) in das Triketon (III) übergeht.

Synthesis of 12.ALPHA. and 12.BETA.-carboxyestradiol derivatives via the thermal elimination of .BETA.-ketosulfoxide.

The unsaturated keto ester (3) prepared from the β-ketosulfoxide (2) by the mild thermal elimination was condensed with 2-methylcyclopentane-1, 3-dione to give the trione (4), which was converted into the novel title compounds (14) and (15).

The regioselective behavior of unsaturated keto esters toward vinylogous amides

The regioselective behavior of unsaturated keto esters toward vinylogous amides

A Facile Synthesis of Conjugatedα-Methylene-δ-valerolactones

A facile synthetic method of variously substituted α-methylene-δ-valerolactones was devised and the growth inhibiting effects of synthesized samples were tested on rice seedlings. Alkylation of enamines (II) with methyl α-bromomethylacrylate (III) provided key intermediates, unsaturated keto esters (IV) which were readily converted to substituted α-methylene-δ-valerolactones (V) by a sequence involving saponification, reduction and lactonization. The growth inhibitory activities of the 6-membered α-methylene lactones synthesized closely paralleled that of α-methylene-γ-phenyl-γ-butyrolactone (XIII) which had already been shown in our previous paper to possess the inhibitory activity comparable to that of the natural inhibitors, heliangine and pyrethrosin.

A Facile Synthesis of Conjugated α-Methylene-δ-valerolactones

A facile synthetic method of variously substituted α-methylene-δ-valerolactones was devised and the growth inhibiting effects of synthesized samples were tested on rice seedlings. Alkylation of enamines (II) with methyl α-bromomethylacrylate (III) provided key intermediates, unsaturated keto esters (IV) which were readily converted to substituted α-methylene-δ-valerolactones (V) by a sequence involving saponification, reduction and lactonization. The growth inhibitory activities of the 6-membered α-methylene lactones synthesized closely paralleled that of α-methylene-γ-phenyl-γ-butyrolactone (XIII) which had already been shown in our previous paper to possess the inhibitory activity comparable to that of the natural inhibitors, heliangine and pyrethrosin.

Thermal isomerization equilibrium between conjugated and unconjugated unsaturated keto-esters

Thermal isomerization equilibrium between conjugated and unconjugated unsaturated keto-esters