Diphosphane, or diphosphine, is an
inorganic compound with the chemical formula P
2H
4. This colourless liquid is one of several binary phosphorus hydrides. It is the impurity that typically causes samples of
phosphine
Phosphine (IUPAC name: phosphane) is a colorless, flammable, highly toxic compound with the chemical formula , classed as a pnictogen hydride. Pure phosphine is odorless, but technical grade samples have a highly unpleasant odor like rotting ...
to ignite in air.
Properties, preparation, reactions
Diphosphane adopts the
gauche conformation
In chemistry, conformational isomerism is a form of stereoisomerism in which the isomers can be interconverted just by rotations about formally single bonds (refer to figure on single bond rotation). While any two arrangements of atoms in a mo ...
(like
hydrazine, less symmetrical than shown in the image) with a P−P distance of 2.219
angstrom
The angstromEntry "angstrom" in the Oxford online dictionary. Retrieved on 2019-03-02 from https://en.oxforddictionaries.com/definition/angstrom.Entry "angstrom" in the Merriam-Webster online dictionary. Retrieved on 2019-03-02 from https://www.m ...
s. It is nonbasic, unstable at room temperature, and
spontaneously flammable in air. It is only poorly soluble in water but dissolves in organic solvents. Its
1H NMR spectrum consists of 32 lines resulting from an A
2XX'A'
2 splitting system.
Diphosphane is produced by the hydrolysis of
calcium monophosphide, which can be described as the Ca
2+ derivative of . According to an optimized procedure, hydrolysis of 400 g of CaP at −30 °C gives about 20 g of product, slightly contaminated with
phosphine
Phosphine (IUPAC name: phosphane) is a colorless, flammable, highly toxic compound with the chemical formula , classed as a pnictogen hydride. Pure phosphine is odorless, but technical grade samples have a highly unpleasant odor like rotting ...
.
Reaction of diphosphane with
butyllithium Butyllithium may refer to one of 5 isomeric organolithium reagents of which 3 are commonly used in chemical synthesis:
* ''n''-Butyllithium, abbreviated BuLi or nBuLi
* ''sec''-Butyllithium, abbreviated ''sec''-BuLi or sBuLi, has 2 stereoisomers, ...
affords a variety of condensed polyphosphine compounds.
Organic diphosphanes
A variety of organic derivatives of diphosphane are known. These species are prepared by reductive coupling, e.g.
tetraphenyldiphosphine
Tetraphenyldiphosphine is the organophosphorus compound with the formula Ph2sub>2, where Ph = phenyl
In organic chemistry, the phenyl group, or phenyl ring, is a cyclic group of atoms with the formula C6 H5, and is often represented by the sym ...
from
chlorodiphenylphosphine
Chlorodiphenylphosphine is an organophosphorus compound with the formula (C6H5)2PCl, abbreviated Ph2PCl. It is a colourless oily liquid with a pungent odor that is often described as being garlic-like and detectable even in the ppb range. It is u ...
:
:2 ClPPh
2 + 2 Na → Ph
2P−PPh
2 + 2 NaCl
The methyl compound P
2Me
4 is prepared by the reduction of Me
2P(S)−P(S)Me
2, which is produced by methylation of
thiophosphoryl chloride
Thiophosphoryl chloride is an inorganic compound with the formula PSCl3.Spilling, C. D. "Thiophosphoryl Chloride" in Encyclopedia of Reagents for Organic Synthesis John Wiley & Sons, Weinheim, 2001. . Article Online Posting Date: April 15, 2001. ...
with methylmagnesium bromide.
See also
*
Pnictogen hydride Pnictogen hydrides or hydrogen pnictides are binary compounds of hydrogen with pnictogen ( or ; from grc, πνῑ́γω "to choke" and -gen, "generator") atoms (elements of group 15: nitrogen, phosphorus, arsenic, antimony, and bismuth) covalently ...
References
Phosphorus hydrides
Foul-smelling chemicals
{{Hydrides by group