Reactive organosilanes

This type of test could be carried out equally well with commercially produced ODS plates. Silica gel plates can be simply modified with reaction with organosilane reagents, the availability of a wide range of reactive organosilanes means that there is potential for producing a wide range of coated TLC plates for specific purposes. 

Evidence that the 1Sn2 reaction at silicon does indeed go through a pentacovalent intermediate comes from the silicon analogue of the migration step in hydroboration-oxidation. Treatment of reactive organosilanes (that is, those with at least one heteroatom—F, OR, NR2—attached to silicon to encourage nucleophilic attack of hydroperoxide at silicon)... 

Figure 6.3 Some examples of functional groups which have been attached to surfaces by use of the corresponding reactive organosilanes.yv represents a generalized linking chemical group such as an alkyl chain.

Silylformylation of terminal alkynes generally occurs under relatively mild conditions to afford a silylolefm. The major side product of this reaction is hydrosilylation. The use of more reactive organosilanes or an increase in the carbon monoxide pressure has been shown to enhance silylformylation. Furthermore, Doyle and Shankin demonstrated that a dirhodium complex can be used to overcome this synthetic problem. Dirhodium(II) perfluorobut3n ate has been shown to give exclusively silylcarbonylation when used with phenylacetylene 70 favoring the cis product with Z E ratios as high as 40 1 (71a and 71b). Additional success with... 

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