Tetrakis disilene preparation

Two A2Si = SiB2-type tetrakis(triakylsilyl)disilenes 36 and 37 were synthesized using Method D [Eq. (4)].14 In the synthetic route, the preparation of hydridosilyl-lithiums 80 by the silametallation of the corresponding dihydridosilanes 79 is involved.15... 

A lithium naphthalenide solution can be prepared by stirring equimolar quantities of naphthalene and lithium in THF. This solution of lithium naphthalenide (0.34 mmol) in THF was added to tetrakis di-fbutylmethylsilyl)disilene (112 mg, 0.16 mmol) in THF 2.5 mL) at -78°C with the help of a syringe. Afterward the reaction mixture was allowed to warm up to room temperature over 2 h. There was a rapid color change resulting in the formation of the 1,2-dianion of the disilene (6). This dianion was further treated with 12-crown-4 (110 irL, 0.69 mmol, 4.3 equiv) at room temperature. Afterward THF was removed in vacuo and hexane was added to the reaction mixture. The hexane solution was filtered and overnight standing at -30°C led to the isolation of silylene anion radical as air- and moisture-sensitive red crystals (128 mg, 56%). Mp 138-139°C (Scheme 6.1.1.1). 

The synthesis of a trisilaallyl cation with an allylic cation character is described. The allylic cations are considered important intermediates in organic transformations. The preparation of the trisilaallyl cationic species, cyclotetrasilenylium ion is performed by the reaction of tetrakis(di-tbutylmethylsilyl) disilene (6) with [EtsSifbenzene)]" - TPFPB TPFPB = tetrakisfpenta-fluorophenyl)borate in toluene (Scheme 6.3.1.1). The cyclotetrasilenylium ion is demonstrated to exist as a cation free of anion interaction in the solid state (5). 

Preparation of tetrakis(di-tbutylmethylsilyl)disilene (Method A) 74 Preparation of tetrakis(di-tbutylmethylsilyljdisilene (Method Bl 75 References 77... 

Preparation of tetrakis(di-tbutylmethylsilyl)disilene (Method B) Apparatus... 

Preparation of [lithiumltetrahydrofuranlj tetrakis(di-tbutylmethylsilyl) disilene anion radical 33 References 34... 

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