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Silanetriols as Powerful Starting Materials for Selective Condensation to Bulky POSS Cages.

ABSTRACT: Controlled condensation reactions of tertiary silanetriols CH₃(CH₂) _n (CH₃)₂CSi(OH)₃ (1b-f; n = 1-5) in the presence of trifluoroacetic acid and the hydrolysis of CH₃(CH₂)₆(CH₃)₂CSiCl₃ (3) lead to the selective formation of the corresponding disiloxane tetrols [CH₃(CH₂) _n (CH₃)₂CSi(OH)₂]₂O (2b-g; n = 1-6) in good yields. The TBAF-driven condensation reactions of the silanetriols CH₃(CH₂) _n (CH₃)₂CSi(OH)₃ (1a-c; n = 0-2) as well as of the disiloxane-1,1,3,3-tetrol 2d (n = 3) yield in the selective formation of the first T₈ cages bearing tertiary carbon substituents, CH₃(CH₂) _n (CH₃)₂C (4a-d; n = 0-3), which was not possible via the condensation of their alkoxysilane counterparts so far. The resulting compounds 2b-g and 4a-d have been characterized by multinuclear NMR, MS, and single-crystal X-ray diffraction.

SUBMITTER: Hurkes N

PROVIDER: S-EPMC4276717 | biostudies-literature | 2014 Dec

REPOSITORIES: biostudies-literature

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Silanetriols as Powerful Starting Materials for Selective Condensation to Bulky POSS Cages.

Hurkes Natascha N Bruhn Clemens C Belaj Ferdinand F Pietschnig Rudolf R

Organometallics 20141203 24

Controlled condensation reactions of tertiary silanetriols CH3(CH2) n (CH3)2CSi(OH)3 (1b-f; n = 1-5) in the presence of trifluoroacetic acid and the hydrolysis of CH3(CH2)6(CH3)2CSiCl3 (3) lead to the selective formation of the corresponding disiloxane tetrols [CH3(CH2) n (CH3)<sub ...[more]

PMID: 25550679

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