Halogenation mixed

Complexes [AuX3(PR3)] are usually prepared by oxidation of the gold(I) derivative [AuX(PR3)j with the corresponding halogen. Mixed halogen complexes can be prepared in a similar way as in equation (70).329 7... 

Free Halogens Mix 10 mL of sample with 10 mL of 10% potassium iodide solution and 1 mL of starch TS. Shake the mixture vigorously for 2 min. A blue color does not appear in the water layer. 

Arsenic-halogen mixed-bridge compounds, R2GaAs-... 

The water is retained by the sulphuric acid, and the SiF4 is freed from HF by passing it over dry NaF. The other silicon tetrahalides are generally made by direct combination with the halogen. Mixed tetrahalides such as SiFgCl and SiClgBrg have also been obtained (Schumb, 1942). 

Arsenic-halogen mixed-bridge compounds, R2GaAs-(SiMe3)2Ga(R)2X, have been prepared by dehalosilylation that involves As(SiMe3)3 and R2GaX (R = Ph, X = Cl, Br R =... 

In contrast with addition of two identical halogens, mixed additions to double bonds can pose regiochemical problems. Is the addition of Br and OH (or OR) to an unsymmetric double bond selective The answer is yes. For example, 2-methylpropene is converted by... 

It is worth noting here that the results of some other studies of aromatie substitutions, sueh as the Friedel-Crafts benzylation and iso-propylation of alkylbenzenes, and the bromination of alkylbenzenes with bromine, eatalysed by ferrie ehloride, are under suspicion as depending upon slow mixing. As regards halogenation eatalysed by Lewis aeids, positive evidenee to support this eritieism has been obtained. ... 

The mix of inductive and resonance effects varies from one halogen to another but the net result is that fluorine chlorine bromine and iodine are weakly deactivating ortho para directing substituents... 

The most important of the halogenated derivatives of acetic acid is chloroacetic acid. Fluorine, chlorine, bromine, and iodine derivatives are all known, as are mixed halogenated acids. For a discussion of the fluorine derivatives see Fluorine compounds, organic. 

Table 7. Chlorinated and Mixed Halogen Additive Flame Retardants...

Olefin and acetylene complexes of Au(I) can be prepared by direct iateraction of the unsaturated compounds with a Au(I) hahde (190,191). The resulting products, however, are not very stable and decompose at low temperatures. Reaction with Au(III) hahdes leads to halogenation of the unsaturated compound and formation of Au(I) complexes or polynuclear complexes with gold ia mixed oxidatioa states. 

Phosphoms forms weU-defined halogen compounds of the types PX, PX, POX, and PSX, all of which except the pentaiodide and the oxy- and sulfoiodides are known. In addition to the binary haUdes, a few of the many possible mixed haUdes, eg, PX2Y and PX2Y2, have been prepared. The commercially important phosphoms haUdes are phosphoms trichloride [7719-12-2] phosphoms oxychloride [10025-87-3] phosphoms pentachloride [10026-13-8] and phosphoms sulfochloride [3982-91-0]. A few other phosphoms haUdes, eg, PI, PR13) marketed as reagent... 

Tin tetrachloride has been used to prepare the stericaHy hindered triisopropylchlorosilane [13154-24-0] (119). Organobromosdanes are obtained under similar conditions through reaction with cupric and mercuric bromide. These reactions are most suitable for stepwise displacement of hydrogen to form mixed hydridochlorosilanes or in systems sensitive to halogen (120). Hydrides have also been displaced using organic bromides. Heating triethylsilane and... 

In general, Grignard reagents are useful in the synthesis of mixed hydridochlorosilanes because these reagents can effect stepwise substitution of the halogen, eg,... 

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