Phosphonium iodide/chloride

Some compounds are named as derivatives of the simple phosphoms hydrides (phosphines). For example, dimethylphosphine [676-59-5], (CH2)3PH triphenylphosphine oxide [791-28-6], (CgH3)3P=0 1,2-dimethyldiphosphine [53684-00-7], CH PHPHCH diethyliodophosphine [20472-47-3], (C2H3)2PI phosphonium iodide [12125-09-6], PH" P tetramethylphosphonium chloride [1941 -19-1], (CH3) P" C1 and phenylphosphonium bromide [55671-96-0], CgH PHjBr-. 

The reaction of higher alkyl chlorides with tin metal at 235°C is not practical because of the thermal decomposition which occurs before the products can be removed from the reaction zone. The reaction temperature necessary for the formation of dimethyl tin dichloride can be lowered considerably by the use of certain catalysts. Quaternary ammonium and phosphonium iodides allow the reaction to proceed in good yield at 150—160°C (109). An improvement in the process involves the use of amine—stannic chloride complexes or mixtures of stannic chloride and a quaternary ammonium or phosphonium compound (110). Use of these catalysts is claimed to yield dimethyl tin dichloride containing less than 0.1 wt % trimethyl tin chloride. Catalyzed direct reactions under pressure are used commercially to manufacture dimethyl tin dichloride. 

In the phosphonium iodide and chloride salt catalyzed TMSCN addition on aldehydes and ketones, a double activation should exist. Not only the activation of the ketones or aldehydes with the phosphonium cation is necessary, but also the activation of the TMSCN by the soft Lewis base [I] or the harder Lewis base [Cl], which can form a pentavalent silicon intermediate [121]. 

The reaction between dry phosphine and hydrogen iodide, first described in 1817 by J. J.Houtonde la Billardiere produces phosphonium iodide. The simplest laboratory preparation of this compound is by the hydrolysis of an intimate mixture of diphosphorus tetraiodide and white phosphorus According to X-ray diffraction investigations, phosphonium iodide crystallises in a caesium chloride type lattice 3m,32s). 326) hydrogen atoms... 

Phosphonium iodide, 4510 Phosphonium perchlorate, 4000 Phosphorous acid, see Phosphonic acid, 4499 Phosphorus azide difluoride—borane, 4310 Phosphorus azide difluoride, 4309 Phosphorus chloride difluoride, 3973 f Phosphorus, 4868... 

Aluminium, 0048 Ammonium phosphinate, 4549 Barium phosphinate, 0210 f Benzaldehyde, 2727 1,4-Benzenediol, 2326 Bis(hydrazine)tin(II) chloride, 4064 Calcium acetylide, 0582 Calcium phosphinate, 3925 Chromium(II) chloride, 4046 Chromium(II) oxide, 4235 Chromium(II) sulfate, 4238 Copper(I) bromide, 0264 Diacetatotetraaquocobalt, 1774 Diisobutylaluminium hydride, 3076 f 1,2-Dimethylhydrazine, 0951 1,2-Diphenylhydrazine, 3511 Dipotassium phosphinate, 4425 f Ethanedial, 0719 f Formaldehyde, 0415 Formic acid, 0417 Gallium(I) oxide, 4405 Glucose, 2513 f Hydrazine, 4515 Hydroxylamine, 4493 Hydroxylaminium phosphinate, 4550 Hyponitrous acid, 4464 Iron(II) chloride, 4055 Iron(II) hydroxide, 4386 Iron(II) sulfate, 4393 Fead(II) phosphinate, 4526 Fead(II) phosphite, 4530 Fithium dithionite, 4682 Magnesium, 4685 Magnesium phosphinate, 4512 Manganese(II) phosphinate, 4514 f Methylhydrazine, 0500 Phenylhydrazine, 2366 Phosphinic acid, 4498 Phosphonic acid, 4499 Phosphonium iodide, 4510 Potassium, 4640 Potassium hypoborate, 0163... 

Phosphine, PHS, also unites with hydrogen chloride, but only under high pressure, at the ordinary temperature. On the other hand, phosphonium iodide, PH4I, is produced by the union of phosphine with hydrogen iodide under atmospheric pressure it forms white, cubical crystals, which, like ammonium chloride, dissociate when heated. The hydrides of arsenic and antimony form no such compounds. 

Phosphine, as remarked on p. 66, combines with hydrogen iodide, forming a salt, PH4I, phosphonium iodide, resembling ammonium chloride. But as it is decomposed by water into phosphine, PH3, and hydrogen iodide, an attempt to convert it into phosphonium hydroxide, PH4OH. cannot be made. Substituted phosphonium compounds,... 

Phosphonitrile chloride, trimeric and tetrameric, 6 94 Phosphonium iodide, 2 141, 143 all-glass apparatus for preparation of, 6 91... 

Patents on the carbonylation of methyl chloride [74-87-3] using carbon monoxide [630-08-0] in the presence of rhodium, palladium, and ridium complexes, iodo compounds, and phosphonium iodides or phosphine oxides have been obtained (26). In one example the reaction was conducted for 35... 

Alkyl chlorides and bromides do not in general react under these conditions. The corresponding phosphonium iodides, however, may be prepared in good yield when no solvent is employed. ... 

Phosphine has far less affinity for hydrogen ion than has ammonia. Its only salts are phosphonium iodide, PH I, and phosphonium chloride, PH4CI, These salts decompose on contact with water, liberating phosphine. 

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