Phosphorus (II) iodide

Structural formula
General
Surname	Phosphorus (II) iodide
other names	Diphosphorus tetraiodide; Tetraiododiphosphine; Tetraiododiphosphine;
Molecular formula	P 2 I 4
Brief description	light red crystals
External identifiers / databases
EC number	236-646-7
ECHA InfoCard	100.033.301
PubChem	83484
Wikidata	Q412973
properties
Molar mass	569.57 g mol −1
Physical state	firmly
Melting point	125.5 ° C
safety instructions
GHS labeling of hazardous substances danger
H and P phrases	H: 314
	P: 280-305 + 351 + 338-310
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Phosphorus (II) iodide is a chemical compound with the molecular formula P ₂ I ₄ . It consists of two phosphorus atoms in the oxidation state +2, which via a single bond connected to each other. Each phosphorus atom also has two bonds to iodine atoms.

presentation

Phosphorus (II) iodide can be obtained from the elements . For this purpose, white phosphorus is reacted with elemental iodine.

{\ displaystyle \ mathrm {P_ {4} \ + \ 4 \ I_ {2} \ longrightarrow \ 2 \ P_ {2} I_ {4}}}

Further possibilities are the iodination of phosphine and the iodination of phosphorus trichloride with potassium iodide .

{\ displaystyle \ mathrm {8 \ PH_ {3} \ + \ 5 \ I_ {2} \ longrightarrow \ P_ {2} I_ {4} \ + \ 6 \ PH_ {4} I}}

{\ displaystyle \ mathrm {PCl_ {3} \ + \ 3 \ KI \ longrightarrow \ PI_ {3} \ + \ 3 \ KCl}}

properties

Phosphorus (II) iodide is a solid compound at room temperature that melts at 125.5 ° C. Phosphorus (II) iodide reacts with bromine to form a mixture of phosphorus triiodide , phosphorus tribromide and the mixed halides PBr ₂ I and PBrI ₂ .

The connection has a triclinic crystal structure with space group P 1 (space group no. 2) . Template: room group / 2

use

Phosphorus (II) iodide can be used for the synthesis of aziridines from amino alcohols.

It is also used to produce nitriles from carboxylic acids .

Individual evidence

^ ^A ^b ^c ^d A. F. Holleman , E. Wiberg , N. Wiberg : Textbook of Inorganic Chemistry . 101st edition. Walter de Gruyter, Berlin 1995, ISBN 3-11-012641-9 .
↑ ^a ^b Data sheet Diphosphorus tetraiodide from Sigma-Aldrich , accessed on April 19, 2011 ( PDF ).
↑ H. Suzuki, T. Fuchita, A. Iwasa, T. Mishina: Diphosphorus Tetraiodide as a Reagent for Converting Epoxides into Olefins, and Aldoximes into Nitriles under Mild Conditions , in: Synthesis , 1978 , 12 , pp. 905-908; doi : 10.1055 / s-1978-24936 .
^ AH Cowley, ST Cohen: The Iodides of Phosphorus. II. The Reaction of Bromine with Diphosphorus Tetraiodide , in: Tetrahedron Letters , 1965 , 4 , pp. 1221-1222; doi : 10.1021 / ic50030a029 .
^ Matthias F. Groh, Ulrike Müller, Ejaz Ahmed, Alexander Rothenberger, Michael Ruck: Substitution of Conventional High-temperature Syntheses of Inorganic Compounds by Near-room-temperature Syntheses in Ionic Liquids. In: Zeitschrift für Naturforschung B. 68, 2013, doi : 10.5560 / ZNB.2013-3141 .
↑ H. Suzuki, H. Tani: A mild cyclization of 2-aminoalcohols to aziridines using diphosphorus tetraiodide , in: Chemistry Letters , 1984 , 13 , pp. 2129-2130; doi : 10.1246 / cl.1984.2129 .
↑ VN Telvekar, RA Rane: A novel system for the synthesis of nitriles from carboxylic acids , in: Tetrahedron Letters , 2007 , 48 , pp. 6051-6053; doi : 10.1016 / j.tetlet.2007.06.108 .

[howi-1] A ^b ^c ^d A. F. Holleman , E. Wiberg , N. Wiberg : Textbook of Inorganic Chemistry . 101st edition. Walter de Gruyter, Berlin 1995, ISBN 3-11-012641-9 .

[Sigma-2] Data sheet Diphosphorus tetraiodide from Sigma-Aldrich , accessed on April 19, 2011 ( PDF ).

[3] H. Suzuki, T. Fuchita, A. Iwasa, T. Mishina: Diphosphorus Tetraiodide as a Reagent for Converting Epoxides into Olefins, and Aldoximes into Nitriles under Mild Conditions , in: Synthesis , 1978 , 12 , pp. 905-908; doi : 10.1055 / s-1978-24936 .

[4] AH Cowley, ST Cohen: The Iodides of Phosphorus. II. The Reaction of Bromine with Diphosphorus Tetraiodide , in: Tetrahedron Letters , 1965 , 4 , pp. 1221-1222; doi : 10.1021 / ic50030a029 .

[DOI10.5560/ZNB.2013-3141-5] Matthias F. Groh, Ulrike Müller, Ejaz Ahmed, Alexander Rothenberger, Michael Ruck: Substitution of Conventional High-temperature Syntheses of Inorganic Compounds by Near-room-temperature Syntheses in Ionic Liquids. In: Zeitschrift für Naturforschung B. 68, 2013, doi : 10.5560 / ZNB.2013-3141 .

[6] H. Suzuki, H. Tani: A mild cyclization of 2-aminoalcohols to aziridines using diphosphorus tetraiodide , in: Chemistry Letters , 1984 , 13 , pp. 2129-2130; doi : 10.1246 / cl.1984.2129 .

[7] VN Telvekar, RA Rane: A novel system for the synthesis of nitriles from carboxylic acids , in: Tetrahedron Letters , 2007 , 48 , pp. 6051-6053; doi : 10.1016 / j.tetlet.2007.06.108 .