Removal of Trimethylsilyl Protective Group

The half-deprotected product was obtained in 65% yield. Of course, such a yield is insufficient from a synthetic point of view, the photovariant of the redox reaction is not simple instrumentally, and the duration of the reaction (5 h) is too long. Nevertheless, this approach is promising, and deserves attention and development. Thus, the photochemical method proved to be successful in the removal of protecting groups based on covalently linked donor-acceptor systems (Lee and Falvey 2000). 

An economical, practical, and environmentally acceptable procedure was elaborated for oxidative deprotection of trimethylsilyl ethers to their corresponding carbonyl compounds. The reaction proceeded in a solventless system, within a short period of time, and yields were good. On irradiation in a conventional microwave for 30 s, trimethylsilyl ether of benzyl alcohol in the presence of mont-morilonite KIO and finely grounded Fe(N03)3 9H2O gave rise to benzaldehyde in 95% yield. The applicability of this method was tested with several aromatic, alicyclic, and aliphatic trimethylsilyl ethers. Duration did not exceed 1 min, and yields were not lower than 80% (Mojtahedi et al. 1999). 

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