Functional Group Transformation of Aminosilanes

Deaminochlorination is a useM method of transforming aminosilanes to chlorosilanes. Deaminochlorination is carried out by treatment of aminosilanes with hydrogen chloride or acetyl chloride (37—39). The sequence of amination of chlorosilane, appropriate transformation, and deaminochlorination shovra that amino groups can be used as protecting groups for chlorosilanes. This elegant method of protection and deprotection was established by Tamao (40). 

Transformation of aminosilane to chlorosilane with hydrogen chloride (24) 

A 2 L three-necked round-bottomed flask, a mechanical stirrer, a bubbling tube, a reflux condenser, a Schlenk Alter funnel, and a Kugelrohr distillation apparatus. 

Hydrogen chloride, 2,2-di-tert-butyl-l-diethylamino-l,1-diphenyl-disilane, diethyl ether, hexane. 

Hydrogen chloride was passed through a solution of 2,2-di-terf-butyl-l-diethylamino-l,l-diphenyldisilane (85.0 g, 214 mmol) in diethyl ether (600 mb) at room temperature for 2 h. A large amount of hexane was added to the reaction mixture. Insoluble materials were Altered off, and the filtrate was evaporated. The residue was distilled with a Kugelrohr distillation apparatus (182°C/0.5 mmHg) to give 2,2-di-terf-butyl-l-chloro-l,l-diphenyldisilane (72.8 g, 94%) as a colorless liquid. 

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