Cyclopentaphosphine is the inorganic compound with the formula (PH)5. It is prepared by the hydrolysis of cyclo-[PSiMe3]4 (Me = methyl). Although only of theoretical interest, (PH)5 is parent of many related cyclic polyphosphines that are the subject of research.

Cyclopentaphosphine
Names
IUPAC name
pentaphospholane
Other names
Cyclopentaphosphane, pentaphosphole
Identifiers
3D model (JSmol)
ChemSpider
EC Number
  • 235-633-3
  • InChI=1S/H5P5/c1-2-4-5-3-1/h1-5H
    Key: MSVKYECZFNAJJY-UHFFFAOYSA-N
  • P1PPPP1
Properties
H5P5
Molar mass 159.909 g/mol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Organic cyclophosphines

edit
 
Structure of (2-pyridylP)5.[1] Color code: maroon = P, black = C, white = H, blue = N.

Organic cyclophosphanes are a family of organophosphorus compounds with the formula (RP)n where R is an organic substituent. Many examples are known. They are white, air-sensitive solids which have good solubility in organic solvents. Well-characterized examples are known for ring sizes 3–6. The three-membered rings feature bulky substituents, e.g., [tert-BuP]3.

The cyclophosphines can be prepared by several methods, one involves reductive coupling of dichlorophosphines:[2]

5 PhPCl2 + 5 Mg → [PhP]5 + 5 MgCl2

Isomerism

edit

The structures are complicated by the slow pyramidal inversion at phosphorus(III). In principle, many isomers are possible for cyclo-P5R5, but usually only one is observed.[3] All phenyl substituents are equatorial in cyclo-P6(C6H5)6.[4]

References

edit
  1. ^ Schoemaker, Robin; Schwedtmann, Kai; Franconetti, Antonio; Frontera, Antonio; Hennersdorf, Felix; Weigand, Jan J. (2019). "Controlled Scrambling Reactions to Polyphosphanes via Bond Metathesis Reactions". Chemical Science. 10 (48): 11054–11063. doi:10.1039/C9SC04501E. PMC 7066665. PMID 32190255.
  2. ^ Marianne Baudler, Klaus Glinka (1993). "Monocyclic and Polycyclic Phosphines". Chem. Rev. 93: 1623–1667. doi:10.1021/cr00020a010.
  3. ^ Hoffman, P. R.; Caulton, K. G. (1975). "Conformational Stability and Ring-Size Integrity of Cyclic Polyphosphines". Inorganic Chemistry. 14 (8): 1997–1999. doi:10.1021/ic50150a051.
  4. ^ Schmutzler, Reinhard; Heuer, Lutz; Schomburg, Dietmar (1993). "Transformations of Difluorophosphines: The Influence of Solvent on the Reaction Pathway and Ring Size in Cyclopolyphosphines". Phosphorus, Sulfur, and Silicon and the Related Elements. 83 (1–4): 149–156. doi:10.1080/10426509308034357.