Tetrahydrofuran → HCID 12927165, compound

Temperature

-76 °C

Under a nitrogen atmosphere a solution of ethyl-2-bromophenyl-3-trifluoromethylphenylphosphonate (2.4 g, 0.00567 mole) in 50 ml. of tetrahydrofuran was cooled to -76° C. in a solid carbon dioxide-acetone bath. To this cooled solution was dropwise added a solution of t-butyllithium (0.74 g, 0.0116 mole) in 6.1 ml. of pentane at a rate such that the temperature of the reaction was maintained below -65° C. The reaction mixture was then stirred for one hour at -76° C. after which time the temperature of the reaction mixture was allowed to rise to 26° C. over a period of 45 minutes. The reaction was quenched with the addition of 1 ml. of acetic acid. The reaction mixture was concentrated to yield a yellow residue which was partitioned between methylene chloride and water. The methylene chloride layer was dried over magnesium sulfate and concentrated in vacuo to yield a yellow glass-like residue. The glass-like residue was distilled to yield a colorless oil which was crystallized upon trituration in petroleum ether to yield 1-[3-(trifluoromethyl)phenyl]-1,3-dihydro-2,1-benzoxaphosphole-1-oxide (0.85 g, 51% yield) as a white solid having a melting point of 102°-106° C. and the following analysis:

1. waitto rise to 26° C. over a period of 45 minutes
2. customThe reaction was quenched with the addition of 1 ml
3. concentrationThe reaction mixture was concentrated
4. customto yield a yellow residue which
5. customwas partitioned between methylene chloride and water
6. dry with materialThe methylene chloride layer was dried over magnesium sulfate
7. concentrationconcentrated in vacuo
8. customto yield a yellow glass-like residue
9. distillationThe glass-like residue was distilled
10. customto yield a colorless oil which
11. customwas crystallized upon trituration in petroleum ether

ORD record

ord-3cda5653759f49dcbfde3de9e208168c

Source dataset

uspto-grants-1980_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04219510