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ChemicalBook CAS DataBase List METHYL 2-(O-NITROBENZYLIDENE)-ACETOACETATE
39562-27-1

METHYL 2-(O-NITROBENZYLIDENE)-ACETOACETATE synthesis

4synthesis methods
-

Yield: 97%

Reaction Conditions:

in acetic acid;isopropyl alcohol

Steps:

4.a (a)
(a) Ylidenecarboxylic ester 116 g (1 mol) of methyl acetoacetate, 151 g (1 mol) of 2-nitrobenzaldehyde, 2.4 g (0.04 mol) of glacial acetic acid and 3.4 g (0.04 mol) of piperidine are added in that sequence, with stirring, to 650 ml of isopropanol at room temperature. The mixture is warmed to 40° C. and kept at this temperature for 15 minutes. It is then cooled to 20° C. and stirred for 16 hours. Subsequently it is cooled to 0° C. and stirred at this temperature for 1 hour. The supernatant solution is then removed by suction, and the crystals are centrifuged with 130 ml of ice-cold isopropanol and removed by suction. The resulting methyl 2-(2'-nitrobenzylidene)acetoacetate is immediately reacted in the same vessel as described in (b). When the methyl 2-(2'-nitrobenzylidene)acetoacetate is isolated and dried, then 241.7 g of yellow crystals (97% of the theoretical yield) of melting point 99°-101° C. are obtained.

References:

Bayer Aktiengesellschaft US4600778, 1986, A

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