Tetraethyl propane-1,1,3,3-tetracarboxylate

The a, jfl-unsaturated component for a Michael reaction may be formed in situ by an initial Knoevenagel reaction. An example is provided by the formation of tetraethyl propane-1,1,3,3-tetracarboxylate (14) from formaldehyde and diethyl malonate in the presence of diethylamine. Diethyl methylenemalonate (13) is first formed by the simple Knoevenagel reaction and this is followed by the Michael addition process. 

Tetraethyl propane-1,1,3,3-tetracarboxylate. Cool a mixture of 320 g (302 ml, 2 mol) of redistilled diethyl malonate and 80 g (1 mol) of 40 per cent formaldehyde solution ( formalin ) contained in a 1-litre round-bottomed flask to 5 °C by immersion in ice, and add 5 g (7 ml) of diethylamine. Keep the mixture at room temperature for 15 hours and then heat under a reflux condenser on a boiling water bath for 6 hours. Separate the aqueous layer, dry the organic layer with anhydrous sodium sulphate and distil under reduced pressure. Collect the tetracarboxylate ester at 200-215 °C/20mmHg. The yield is 250 g (75%). 

Diethyl sodio malonate Tetraethyl cthane-l,l,2,2-tetracarboxylate, hexaethyl (EtOH, DMSO, DMF) propane-1,1,2,2,3,3-hexacarboxylate (main product... 

C1SH24O8 propane-l,l,2,3-tetracarboxylic acid tetraethyl ester 635-03-0... 

C15H24 08 propane-1,1,3,3-tetracarboxylic acid tetraethyl ester 2121-66-6... 

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