Reaction #1849993

Reaction equation

diethyl malonate

potassium hydroxide

dimethylsulfoxide

N,N'-dimethylethylenediamine

dithiolate

→

desired product

Yield 24.0%

Diethyl(1,2,5-trimethyl-2,5-diaza-7,9-dithiabicyclo-[4,3,0]-nonane-8-ylidene)malonate

Yield 24.0%

Solvents

carbon disulfide

water

water

Conditions

Workup

1. 1
   workup.ADDITIONwas added dropwise at 0° C.
2. 2
   workup.STIRRINGAfter the reaction mixture was stirred for additional 1 hour
3. 3
   OtherThe solid precipitated
4. 4
   Filtrationwas collected by filtration
5. 5
   Otherrecrystallized from ethyl acetate-n-hexane

Procedure

In 40 ml of water was suspended 11.2 g of pyruvic aldehyde sodium bisulfite addition compound, and 2.3 g of N,N'-dimethylethylenediamine was added dropwise at 0° C. and the mixture was stirred for additional 1 hour. To this solution was added dropwise at 0° C. the dithiolate solution, which had been prepared previously by the reaction of 3.2 g of diethyl malonate with 1.8 g of carbon disulfide in 20 ml of dimethylsulfoxide in the presence of 9.7 g of 30% aqueous potassium hydroxide. After the reaction mixture was stirred for additional 1 hour, 50 ml of water was added to the solution. The solid precipitated was collected by filtration and recrystallized from ethyl acetate-n-hexane to give 1.7 g of the desired product.

Source