New CF 3 Substituted Phosphorus‐Tellurium Heterocycles

The reaction of trifluormethyl dichlorophosphine (CF 3 PCl 2 ) with sodium telluride Na 2 Te or bis(trimethylsilyl) telluride (Me 3 Si) 2 Te results in the formation of four new phosphorus tellurium heterocycles ( 1–4 ) with the electron withdrawing CF 3 substituent bonded to phosphorus. The telluratriphosphetane (CF 3 P) 3 Te ( 1 ), telluratetraphospholane (CF 3 P) 4 Te ( 2 ), telluradiphosphirane (CF 3 P) 2 Te ( 3 ) and ditelluratriphospholane (CF 3 P) 3 Te 2 ( 4 ) are characterized by multinuclear ( 31 P, 19 F and 125 Te) NMR spectroscopy. A full analysis of the 19 F NMR spectrum of telluratriphosphetane (CF 3 P) 3 Te is presented. The new heterocycles are remarkably stable in solution and eliminate only slowly tellurium to form cyclophosphines (CF 3 P) n ( n = 3–5).