Various complexes of boron trifluoride and typical organo-phosphorus compounds have been investigated using proton and fluorine resonance (at variable temperature) and boron and phosphorus resonance. In BFs, boron resonance is insensitive to the complex strength, but fluorine resonance suggests the possibility of various types of complexes on the phosphorus group or, additionally on the heteroatoms (e.g. oxygen, nitrogen) of the molecule. These complexes are probably u type. Proton chemical shifts in the organo-phosphorus compounds follow the same trends as in similar complexes of amines, esters etc.; these perturbations may be mainly due to magnetic anisotropy effects; proton-phosphorus couplings conversely follow changes in phosphorus electronegativity .
RBsume--On a ktudie, en resonance du proton et du fluor (a temperature variable) ainsi qu'en resonance du bore et du phosphore, un certain nombre de complexes entre BF, et des composks organo-phosphor& typiques. En ce qui concerne BFs, la resonance du bore reste insensible B la force du complexe; par contre, la resonance du fluor suggkre I'existence de plusieurs types de complexes, soit sur le groupe phosphor&, soit sur les hktkroatomes (par example N , 0) de la molkcule.
* Etude par RMN de composks organo-phosphores XVIII. Article prtckdent: M. J. Green et G. Mavel, Chem. Cornmun. 742 (1968).
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