Phosphorus pentachloride molecular structure

The question of whether the phosphonitrilic chlorides have cyclic or linear structures has been frequently discussed in the literature. The structural evidence will be considered in Section lY, where it will be seen that the cyclic formulation is established beyond doubt for the trimer and tetramer, and is highly probable for the higher soluble polymers it will meanwhile be assumed for all compounds of formula (PNX2) . For reasons considered in Section II, C the petrol-insoluble fraction (PNCUln PCls is believed to consist of a mixture of linear polymers. The two series are related, in that the linear compounds of low molecular weight are intermediates in the formation of the cyclics by the ammonolysis of phosphorus pentachloride. 

In contrast to the low yield when hydrogen chloride is employed, an 88% yield of 2,4,6-triphenyl- 1,3,5-triazine (7) is obtained when chlorosulfonic acid is used as catalyst in a molecular ratio of 3 1 (CiSOjH/PhCN) at 0-5 C C and a reaction time of 12 to 24 hours.174 Trifluo-romethanesulfonic acid as a catalyst and solvent trimerizes benzonitrile at 91 °C in a yield of 66%.175 Lewis acids alone, such as aluminum, zinc, iron or titanium chlorides, phosphorus pentachloride, and boron trifluoride, have a considerably lower catalytic activity than the corresponding mixtures of Lewis acid with various promotors, such as mineral acids, organic acids and water. These differences are attributed to a change in the structure of the active complexes with the aryl cyanides. 

Phosphorus pentachloride, a key industrial compound with annual world production of about 2X lO kg, is used to make other compounds. It reacts with sulfur dioxide to produce phosphorus oxychloride (POCI3) and thionyl chloride (SOCI2). Draw a Lewis structure and name the molecular shape of each product. 

A chiral example of phosphazene bases was synthesized by treatment of (5)-2-(dialky-laminomethyl)pyrrolidine derived from 5-oxo-(5)-proline, with phosphorus pentachloride and subsequent addition of gaseous ammonia. The phosphazenes were isolated as HBF4 salts in high yields and fully characterized by H, and P NMR spectroscopy, various ID and 2D NMR experiments and mass spectrometry (El). The molecular structure and the absolute configuration of the HBF4 salts were determined by X-ray analysis [16]. 

The gas phase molecular structures of phosphorus pentafluoride and pentachloride... 

CONTEXT Phosphorus pentachloride, PF5, is a popular molecule in general chemistry classes for exemplifying the trigonal bipyramidal shape in VSEPR theory The structure is highly symmetric, having two equivalent axial fluorines (so-called because they lie on the principal rotational axis of the molecule) and three equivalent equatorial fluorines. However, studies of the molecular symmetry led to the discovery of an unexpected type of molecular motion. 

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