Methoxymethyl-triphenylphosphonium chloride → HCID 70002150, compound

Temperature

-75 °C

14.27 g (1.6 eq.) of (methoxymethyl)triphenylphosphonium chloride was suspended in 50 ml of abs. THF and deprotonated at a temperature of −10° C. and −5° C. by adding via syringe 25.2 ml of 1.6 M n-butyllithium (1.55 eq., in hexane). The resultant red ylide solution was cooled to −75° C. and treated with 6.20 g (26.0 mmol) of 8-bromo-3,4-dihydro-2H-benzo[b]oxepin-5-one dissolved in 13 ml of abs. THF. The mixture was then kept for 0.2 h at −78° C. and for 1 h at room temperature, poured onto crushed ice and extracted with diethylether. The organic phase was washed with water and dried over magnesium sulfate, filtrated and the solvent evaporated to yield a crude product which was purified by flash chromatography (SiO2, hexane/ethylacetate=95/5). Thereby, 5.85 g of 8-bromo-5-methoxymethylene-2,3,4,5-tetrahydrobenzo[b]oxepine was obtained as E/Z-mixture which was hydrolyzed as follows:

1. customdeprotonated at a temperature of −10° C. and −5° C.
2. dissolutiondissolved in 13 ml of abs
3. additionpoured
4. customonto crushed ice
5. extractionextracted with diethylether
6. washThe organic phase was washed with water
7. dry with materialdried over magnesium sulfate
8. filtrationfiltrated
9. customthe solvent evaporated
10. customto yield a crude product which
11. customwas purified by flash chromatography (SiO2, hexane/ethylacetate=95/5)

ORD record

ord-ecab08880bb643ca978b66044614fc1c

Source dataset

uspto-grants-2002_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06479670B1