Cyclic silanols

Host 24 also stabilises highly reactive cyclic silanol oligomers by a similar in situ synthesis [66]. Phenyltrimethoxysilane, 26, rapidly forms polymeric material in aqueous solutions. The presence of 24 prevents this from occurring and isolates the cyclic trimer intermediate, 27. Several molecules of the silane starting... 

The stabilisation of a highly reactive cyclic silanol oligomer, isolating it from the surrounding media, thus preventing hydrolysis. 

Higher-Yield Synthesis of Cyclic Silanols c/s,c/s,c/s-1,3,5,7-Tetrahydroxy-1,3,5,7-tetraisobutylcyclotetrasiloxane 413... 

SYNTHESIS OF CYCLIC SILANOLS C/S C/ C/S-1,157-TETRAH YDROXY-1,3,5,7-TETRAISOPROPYLCYCLO TETRASILOXANE... 

This method can be applied to isobutyl- or phenyl-substituted cyclic silanols. However, following the method shown in the next section usually gave better yields. 

HIGHER-YIELD SYNTHESIS OF CYCLIC SILANOLS CIS.CIS,CIS-. 2S. TETRAHYDR0XY-1,3,57-TETRAIS0 BUTYLCYCLOTETRASILOXANE... 

After our report of all-cis cyclic silanols, Shchegolikhina s group reported the synthesis of cyclic silanols via sodium or potassium cyclic silanolates from substituted trialkoxysilanes (1). Overall yields are better than those by hydrolytic condensation of tri-chlorosilanes. Kawakami s group applied this method and reported the synthesis of phenyl and isobutyl cyclic silanols (2). We slightly modified Kawakami s method and obtained all-cis-[/-PrSi 0H)0]4 in 74% yield. 

This method can be applied to a wide variety of alkyl- or aryl-cyclic silanols with methyl to bulky substituents. 

This method can be applied to terf-butyl-substituted cyclic silanols. 

This method can be applied to the synthesis of cage octasilses-quioxanes when respective cyclic silanols are available as precursors. 

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