Characterization and molecular structure of 1-hydro-2,8,9-trioxa-1-phospha-5-aza-tricyclo[3.3.3.0]undecane tetrafluoroborate. Pentacoordination of phosphorus

The characterization and molecular structure of (HP(OCH/sub 2/CH/sub 2/)/sub 3/N)BF/sub 4/ reported herein indicated the presence of an N ..-->.. P coordinate bond conferring a trigonal bipyramidal geometry on the P atom. X-ray diffraction techniques were employed to characterize the compound, and the data indicated that the crystal belonged to the orthorhombic crystal class. The angle measurements determined for the trigonal bipyramidal P atom were O-P-O, 120/sup 0/, O-P-N, 87/sup 0/, and H-P-N, 172/sup 0/. The value determined for the P reverse arrow N dative bond (1.986 A) is quite comparable to those found in reported six-coordinate systems. (BLM)