PREPARATION AND STRUCTURES OF SOME INTRAM OLECULAR DONOR-ACCEPTOR COMPLEXES WITH THE PHOSPHORYL GROUP AS DONOR

The reaction of henyl-1-(trimethylsiloxy)ethenyl]dimethylphosphane oxi de (1) with PF5 yields 2, involving hexacoordinated phosphorus, by cle avage of the Si-O bond and elimination of (CH3)3SiF. The same compound was formed in the reaction of 1 with RPF4 (R = dimethylamino, morphol ino) by cleavage of the P-N bond and elimination of the corresponding silylated amine, R2NSiMe3. The reaction of 1 with F3B . OEt2 led to th e intramolecular donor-acceptor-complex 3 with a tetracoordinated boro n atom. The complex 4 with penta- (or hexa)coordinated tin was prepare d by reaction of 1 with tin(IV) chloride with elimination of (CH3)3SiC l. X-ray structure analyses of 2 and 3 confirm the donor-acceptor inte raction between the oxygen atom of the P=O group and the PF4 or BF2 gr oup.