Mesoxalic esters

Condensation of y-picoline with mesoxalic ester yielded 4-(j8,j8-diethoxycarbonylvinyl)pyridine (35). The unsaturated ester (35) was hydrogenated with platinum catalyst to form 36 which was treated with bromine. 4-(j8-Bromo-j8,j8-diethoxycarbonylethyl)-piperidine (37) was obtained and was cyclized with pyridine to 2,2-die th 0 xycarbony 1 quinuclidine (38). Hydrolysis of 38 and partial decarboxylation gave quinuclidine-2-carboxylic acid (39). 

During the last years the reaction of 0-sulfonylated oximes with amines was applied repeatedly.It gives diaziridines even from electron-poor carbonyl compounds, which had not been accessible so far. For example, diaziridine 91 is obtained from the 0-tosyl oxime of mesoxalic ester (90). ... 

An alternative proposal for the transition state of the ene reaction involving carbonyl groups, specifically mesoxalic esters, has been advanced. On the basis of little variation in the primary kinetic deuterium isotope effect (2.55 at 120 nC and 2.58 at 200 °C) it was concluded that the transition state involved a C-H-O arrangement significantly distorted from linear and involving participation of a lone-pair of electrons on oxygen as well as secondary orbital overlap7,8. 

Condensation of o-phenylenediamines with mesoxalic ester (5) followed by hydrolysis and decarboxylation of the product yields quinoxalin-... 

Thus biacetyl is obtained by treating 2-butanone with isopentyl nitrite and hydrolysing the resultant diketone monoxime (without isolating it) with sulfuric acid.348 The intermediate need also not be isolated when malonic ester is converted into mesoxalic ester by nitrous gases.349... 

The Martinet reaction is the conversion of primary or secondary anilines in combination with a mesoxalic ester to give an isolable 3-hydroxy-3-carboxy-oxindole (3) which, depending on the reaction conditions, can be converted to either an isatin (4) or the corresponding 3-hydroxyoxindole (5) with a base such as potassium hydroxide. ... 

While no detailed mechanistic studies have been reported, a reasonable mechanism has been proposed previously. Under acid conditions, the aniline and mesoxalic esters likely exist in equilibrium with a Schiff s base such as 6. However, an anilide (8) also can form irreversibly, which then undergoes an intramolecular Friedel-Craft-type alkylation to give an isolable 3-hydroxy-3-carboalkoxy-oxindole such as 10 at elevated temperatures. The... 

Tetrahydroquinolines are also reported to react in a Martinet fashion with mesoxalic esters to give condensed tricycles such as 24. a- and P-Amino-napthalenes have been reported to participate in the reaction as well,... 

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