Preparation, Reactions, and NMR Studies of 4-Methyl-4-Phospha-Tetracyclo [3.3.0.02,8.03,8] Octane 4-Oxide and Derivatives

TLDR: The tetracyclic phosphonium chloride (PCL) was synthesized by treatment of norbornadiene with CH3PCl2 at 65-80°C for one week as mentioned in this paper.

Abstract: The title compound which we1 and others2 have previously synthesized has now been extensively investigated. The tetracyclic phosphonium chloride 1 was prepared by treatment of norbornadiene with CH3PCl2 at 65–80°C for one week. Treatment of 1 with AICl3/CH2CI2 gave 2. Direct or “Inverse” addition at water to 2 dictated the stereochemistry of the oxide 3. Stereoassignments of 3 were made based on lanthanide shift −1H and 13C nmr studies studies. Extensive 2-D nmr studies (HETCOR, COSY) and triple irradiation experiments enabled chemical shift and coupling constant assignments.