Silylamine functionalities

Using the silylamine-functionalized 1,1-diphenylalkyllithium initiator, 39, to polymerize styrene, the corresponding functionalized poly(styryl)lithium, 40 (see Scheme 18), was reacted with MDDPE to form the silyl-amine-functio-nalized, 1,1-diphenylethylene-functionalized polystyrene macromonomer (82) as shown in Scheme28 [212]. Less than 2% dimer formation was observed by SEC. 

The chlorosilanes are clear Hquids that should be treated as strong acids. They react readily with water to form corrosive HCl gas and Hquid. Liquid chlorosilanes and their vapors are corrosive to the skin and extremely irritating to the mucous membranes of the eyes, nose, and throat. The nitrogen-functional silanes react with water to form ammonia, amines, or amides. Because ammonia and amines are moderately corrosive to the skin and very irritating to the eyes, nose, and throat, silylamines should be handled like organic amines. Trimethylsilyl trifluoromethanesulfonate and trimethylsilyl iodide form very corrosive acidic products. 

Interesting variations of these reactions are observed when the a-silylamine donor funtion is tethered to an enone. For example, the intramolecular ET reaction of 143 results in two divergent cyclizations. Methanol assists the cleavage of the C—Si bond the resulting biradical anion 146 couples protonation and tautomer-ization then leads to 147. In acetonitrile, on the other hand, transfer of an a proton to the enone radical anion function forms biradical 144 coupling and tautomer-ization then generates 145. " ... 

An interesting example of the highly enantioselective hydrosilylation of imines has been reported by Buchwald and co-workers. A titanium fluoride complex, (5,5)-(EBTHI)TiF2, catalyzes the formation of silylamines in high yields, with good tolerance of functional groups [Eq. (75)].187... 

Two examples are found for the preparation of a-silylamine derivatives by nucleophilic displacement of an oxygen functionality by an amino compound.88 96... 

Keywords functionalized siloxanes, cyclosiloxanes, silanols, silylamines, aminosiloxanes, metalamidosiloxanes... 

Again, no reaction was observed in the absence of mercaptoethanol. The mechanistic steps for the transformation were elucidated by the Chatgilialoglu et ah and are represented in Scheme 4.13, in analogy with the pathway reported for the radical reduction of aromatic azides with triethylsilane in toluene, with the addition of silyl radicals to the azide function, liberation of nitrogen and formation of silyl-substituted aminyl radical. The thiol is the hydrogen atom donor to this intermediate and it can be regenerated by its interaction with the silane, thus propagating the chain. The hydrolysis of the silylamine occurred... 

Reductive carbonylation of 1,1-dibromocyclopropanes with tetracarbonylnickel in dimethyl-formamide in the presence of a nucleophile is a powerful method for direct introduction of carboxylic acid functions to cyclopropanes. Nucleophiles, such as alcohols, amines, and silylamines, are particularly reactive and give cyclopropyl esters and amides, respectively, in reasonable to good yields, e.g. formation of 5 and... 

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