Pyridine → HCID 12579200, compound

Temperature

3 °C

To a stirred mixture of isopropylidene malonate (5.00 g, 34.7 mmol) in anhydrous dichloromethane (15 ml), cooled under nitrogen to 3° C., was added dropwise, over 7 min, dried pyridine (6.81 ml, 84.2 mmol). The resulting colourless solution was stirred at 3° C. for 3 min, then a solution of hydrocinnamoyl chloride (5.00 ml, 33.7 mmol) in anhydrous dichloromethane (13 ml) was added dropwise over 2.5 h, whilst maintaining the temperature below 6° C. The resulting orange cloudy mixture was stirred at 3° C. for 1 h, then at room temperature for 2.5 h. The mixture was diluted with dichloromethane (20 ml) and poured into ice-cold 1M aqueous HCl (42 ml). The aqueous layer was further extracted with dichloromethane (2×25 ml), and the combined organic extracts were washed with 1M aqueous HCl (2×25 ml), then saturated aqueous NaCl (25 ml), dried (Na2SO4) and evaporated in vacuo to leave 9.06 g of crude 5-benzylacetyl-2,2-dimethyl-1,3-dioxane-4,6-dione as an orange oil.

1. additionwas added dropwise, over 7 min
2. temperaturewhilst maintaining the temperature below 6° C
3. stirringThe resulting orange cloudy mixture was stirred at 3° C. for 1 h
4. waitat room temperature for 2.5 h
5. extractionThe aqueous layer was further extracted with dichloromethane (2×25 ml)
6. washthe combined organic extracts were washed with 1M aqueous HCl (2×25 ml)
7. dry with materialsaturated aqueous NaCl (25 ml), dried (Na2SO4)
8. customevaporated in vacuo

ORD record

ord-7c54c11cd3ef44bfbc842e0b84beb718

Source dataset

uspto-grants-2001_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06333336B1