ChemicalBook CAS DataBase List DBU

DBU synthesis

10synthesis methods

Product Name:DBU
CAS Number:6674-22-2
Molecular formula:C9H16N2
Molecular Weight:152.24

The synthesis of DBU is as follows:As a base, sodium hydroxide was used at a concentration of 25% by weight and 2.3 times molar equivalent. A stirrer was placed in a 100 mL screw tube, and 11.5 g (50 mmol) of DBU hydrochloride, 8.5 g of toluene and 18.5 g (116 mmol) of 25% sodium hydroxide aqueous solution were charged at room temperature. It was placed on a magnetic stirrer and mixed for 1 hour with stirring. The mixture was separated with a 100 mL separatory funnel to obtain 18.8 g of the upper layer containing DBU and 18.4 g of the lower layer of the aqueous layer. The upper layer portion was analyzed by gas chromatography and contained 31.9% by weight of DBU, and the yield was 6.0 g (39.4 mmol) in a yield of 78.8%.

24566-95-8 Synthesis

24566-95-8
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$68.00/100mg

6674-22-2
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$5.00/10g

Yield:6674-22-2 91.7 %

Reaction Conditions:

with toluene-4-sulfonic acid in water at 150 - 160;Dean-Stark;chemoselective reaction;Reagent/catalyst;Temperature;

Steps:

3; 6-7 Example 3: Dehydration of crude amine solution in xylene

To 159.4 g of solution obtained as described in example 2, 1.3 g of p- toluenesulphonic acid monohydrate was added. This mixture was heated to 150- 160°C by reflux through the use of a dry-half spherical heater connected to a temperature controller; the reaction flask was connected to a Dean-Stark trap and a condenser to remove the water produced from the reaction environment: the vapours produced condensed on top of the trap and the water thus formed was removed by gravity into the trap (the solvent fell back into the flask maintaining an almost constant volume). After 4 h from the start of reflux, no further accumulation of water was observed in the trap and the reaction was considered to be complete, then allowed to cool to room temperature. The resulting solution was neutralised with 800 mg of aqueous NaOH solution (min. concentration 45%). GC-MS analysis calculated a conversion of N-(3-aminopropyl)-ε- caprolactam of 92.3%, a selectivity of 99.4% and thus a DBU yield of 91.7%.

References:

WO2022/189911,2022,A1 Location in patent:Page/Page column 24-26; 29