SUBSTITUTIONSREAKTIONEN DES 4,5-BENZO-2-CHLOR-3-METHYL-6-OXO-1,3,2-OXAZAPHOSPHINANS; MOLEKÜLSTRUKTUREN VON γ³P-DERIVATEN

Abstract

The previously known precursor 4,5-benzo-3-methyl-6-oxo-1,3,2-oxazaphosphinane 1 was additionally characterized by single crystal X-ray structure analysis. The reaction of 1 with excess dry sodium fluoride furnished 2. The reaction of 1 with bromotrimethylsilane and iodotrimethylsilane, respectively, led to the products 3 and 4. The reaction of 1 with dimethylaminotrimethylsilane yielded the dimethylamino derivative 5. The derivatives 6–8 were prepared in a similar fashion via the appropriate trimethylsilyl precursors. The δ(³¹P) values of the halogen derivatives 1–4 increase with halogen size. The hydrolytic stability decreases in the order 2–1–3–4. The structures of 2 and 8 were confirmed by single-crystal X-ray structure analysis. 1, 2 and 8 all show envelope conformation with an exposed phosphorus atom.

Key Words:

• 4,5-Benzo-3-methyl-6-oxo-1,3,2-oxazaphosphinane derivatives
• halogen substitution
• dialkylamino substituents
• X-ray structures