Hexane → HCID 11416350, compound

Temperature

2.5 °C

An oven dried three-necked 2 L round bottom flask was equipped with a mechanical stirrer, a thermometer, an N2 inlet, and a septum. The flask was charged with 180.71 g (0.689 mol) of triphenyl- phosphine and 925 mL of CH2Cl2. The reaction mixture was stirred under an N2 atmosphere and cooled to 0-5° C. with an external ice-water bath. The septum was then removed and 114.25 g (0.344 mol) of carbon tetrabromide was added in portions through the open neck of the flask at a rate that maintained the temperature of the reaction mixture below 20° C. After the addition was complete the reaction was stirred for 1 h and then a solution of the (S)-3-benzyloxy-2-methylpropanal from the previous step dissolved in 150 mL of CH2Cl2 was added via cannula over a 5 min period. The reaction mixture was stirred under N2 for an additional 1 h and allowed to warm to room temperature. A separate 10 L three-necked round bottom flask was equipped with a mechanical stirrer and charged with 4 L of hexane. The stirrer was started and the crude reaction mixture was introduced as a slow stream which resulted in formation of a granular precipitate. After the transfer was complete the reaction mixture was filtered and the solids were carefully washed with hexane. The filtrate was evaporated in vacuo and additional solids were deposited. The residue was resuspended in hexane, filtered and the filtrate reevaporated. The resulting oil was purified by Kugelrohr distillation to afford 46.54 g of the title compound as an oil.

1. customAn oven dried three-necked 2 L round bottom flask was equipped with a mechanical stirrer
2. customThe septum was then removed
3. temperaturethat maintained the temperature of the reaction mixture below 20° C
4. additionAfter the addition
5. stirringwas stirred for 1 h
6. additionwas added via cannula over a 5 min period
7. stirringThe reaction mixture was stirred under N2 for an additional 1 h
8. temperatureto warm to room temperature
9. customA separate 10 L three-necked round bottom flask was equipped with a mechanical stirrer
10. customthe crude reaction mixture
11. additionwas introduced as a slow stream which
12. customresulted in formation of a granular precipitate
13. filtrationwas filtered
14. washthe solids were carefully washed with hexane
15. customThe filtrate was evaporated in vacuo and additional solids
16. filtrationfiltered
17. customthe filtrate reevaporated
18. distillationThe resulting oil was purified by Kugelrohr distillation

ORD record

ord-d50f4c912d6a458a94b0bad618db93fc

Source dataset

uspto-grants-2001_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06228867B1