Controlled partial hydrolysis of spherosilicate frameworks: syntheses of endo-[(Me3SiO)6Si6O7(OH)4] and endo-[(Me3SiO)6Si6O7{OSiMe2(CHCH2)}4] from [(Me3SiO)6Si6O9]

Abstract

Readily available (RMe₂SiO)₆Si₆O₉ (3 R = Me, 5 R = CHCH₂); reacts cleanly with aqueous NEt₄OH in THF to afford endo-C_2h-(RMe₂SiO)₆Si₆O₇(OH)₄ (7 R = Me, 9 R = CHCH₂); exhaustive silylation of 7 with (CH₂ CH)- Me₂SiCl/NEt₃ affords endo-C_2h-(Me₃SiO)₆Si₆O₇[OSiMe₂(CHCH₂)]₄ (10).