H/Cl exchange reaction

Both disilanes were stable for weeks at room temperature, but underwent rapid H/Cl exchange reactions and SiSi cleavage upon the addition of traces of catalysts such as AlClj [3]. 

Reactions of silicon hydrides with m-(R3P)2PtCl2 (R = Bu, Ph) have been widely investigated. Alkyl- and aryl-silanes underwent metathetical H/Cl exchange [Eq, (18) (R = Et, Ph, PhCHj, C.H.j)] (55). 

Until relatively recently, less attention has been given to catalysis of redistribution reactions by transition metal complexes. Redistributions have been observed during the course of platinum-catalyzed hydrosila-tion hence, the scrambling reaction can be a nuisance by decreasing the yield of desired hydrosilation products. A noteworthy example is the H/Cl exchange that occurs during the hydrosilation of allyl chloride [Eq. (10)]. 

Treatment of 3 with PdCb resulted in an H/Cl-exchange at both the silicon and the tungsten, leading to the known complex 7a [10] (Scheme 2). 7b was obtained by reaction of 6 with a hi excess of ecu in 87% yield. 

A typical reaction of metal hydride complexes is the conversion to the corresponding halogeno compounds. This is exemplarily illustrated by the clean H/Cl exchange with CCU on 5 to Cp2Mo(Cl)Si(OEt)3 9. The reverse conversion can be done by hydrogenation with LiAlH4 (Eq. 3). 

In addition to C/C exchanges, catalytic C/H, H/D, C/Cl, H/Cl, C/O, Si/C and Si/Si exchanges are known. These reactions have been used to make new monosilane derivatives, Si-Si bonded compounds and siloxane polymers39. An example of a selective Me/Cl exchange reaction is shown in equation 1083O°. 

C-Cl bonds in the same reaction led to the development of a highly efficient catalytic Si-H/C-Cl exchange reaction (Eq. 3) [9]. 

Depending on the nature of olefins, hydrosilanes, and catalysts, side reactions can also occur, such as H-Cl exchange in silanes as well as hydrogenation and olefin isomerization (144,145). In some cases, in the reaction catalyzed by some complexes of ruthenium, rhodium, iron, iridium, platinum, and nickel, alkenylsilanes have been obtained as a major product of the dehydrogenative... 

The potential barrier of the H + FH exchange reaction (33.5 kcal/mol) was used to obtain the adjustable parameters. The potential barriers of other H + XH (X = Cl, Br, I) exchange reactions were obtained using these parameters. 

As the optimal H-Cl distance remains very close to its value in the isolated molecule also when approaching H2O, the proton exchange reaction H2O + HCl H30 + Ch results energetically unfavourable as further confirmed hy the data reported in the following paragraph. 

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