Trimethylsilanol, synthesis

In the first total synthesis of thromboxane A2, lactone 340 is opened by potassium trimethylsilanolate 97 to give the potassium salt 341 [120]. The potassium salt of the methoxymethyl ether of salicylic acid is prepared likewise [121], as are... 

The synthesis of poly(dimethylsiloxane)macromonomers was also carried out anionically. The cyclic trimer D3 of dimethylsiloxane may be polymerized anionically, using lithium trimethylsilanolate as the initiator. Deactivation of the silanolate end groups may be performed with chlorosilyl functions. Yamashita et al. 29) successfully applied the unsaturated deactivators I and II... 

The Peterson olefination is a connective alkene synthesis and represents a useful alternative to the Wittig reaction. The precursors for the Peterson olefination are 3-hydroxy-alkyltrimethylsilanes which undergo P-elimination of trimethylsilanol under basic or acidic conditions to furnish stereodefined alkenes. This olefination method is especially valuable for the preparation of terminal and exo-cyc ic double bonds and for the methylenation of hindered ketones where the Wittig reaction is problematic. Also, the... 

Diazomethyltrimethylsilane, (CHa)3SiCHN2, can be used in this synthesis with comparable results. A possible mechanism for this reaction involving loss of nitrogen with Wolff rearrangement and then loss of lithium trimethylsilanolate from the initial adduct is shown in equation (III). 

The modification of the Peterson reaction using an N-trimethylsilylamide anion instead of an a-silyl carbanion offers a promising route to the corresponding imines. Treatment of N-(p-tolyl)-N-trimethylsilylamide anion with carbonyl compounds yields the corresponding ketimines [400]. In particular, LiHMDS has been utilized for the preparation of N-trimethylsilylimines, which are useful as masked imine derivatives in the synthesis of yS-lactam antibiotics [401-407]. Reactions of LiHMDS with non-enolizable aldehydes, enolizable aldehydes, ketones, a diketone, and a-keto esters give the respective imines (Scheme 2.153) [408-413]. Chloro-trimethylsilane is added to convert the generated lithium trimethylsilanolate into hexamethyldisiloxane. 

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