%0 Generic
%A Fujdala, Kyle L.
%A Oliver, Allen G.
%A Hollander, Frederick J.
%A Tilley, T. Don
%D 2003
%T Tris(tert-butoxy)siloxy Derivatives of Boron, Including the Boronous
Acid HOB[OSi(OtBu)3]2 and the Metal (Siloxy)boryloxide Complex
Cp2Zr(Me)OB[OSi(OtBu)3]2: A Remarkable Crystal Structure with 18
Independent Molecules in Its Asymmetric Unit
%U https://acs.figshare.com/articles/dataset/Tris_i_tert_i_-butoxy_siloxy_Derivatives_of_Boron_Including_the_Boronous_Acid_HOB_OSi_O_i_sup_t_sup_i_sup_sup_Bu_sub_3_sub_sub_2_sub_and_the_Metal_Siloxy_boryloxide_Complex_Cp_sub_2_sub_Zr_Me_OB_OSi_O_i_sup_t_sup_i_sup_sup_Bu_sub_3_sub_sub_2_sub_A_Remarka/3606636
%R 10.1021/ic0205482.s001
%2 https://acs.figshare.com/ndownloader/files/5694678
%K N 2 porosimetry
%K BOH
%K Bu
%K BOSi 3 epe
%K BOSi 2 epe
%K Et 2 O
%K TEM
%K Remarkable Crystal Structure
%K H 2 O
%K BOSi 3 xg
%K uniform particle sizes
%K block copolymer template
%K crystal structure
%K 18 Independent Molecules
%K transition metal boryloxide
%K Asymmetric Unit Silanolysis
%K Cp 2 ZrMe 2
%K BOSi 2 xg
%K HOB
%X Silanolysis of B(OtBu)3 with 2 and 3 equiv of HOSi(OtBu)3 led to the formation of tBuOB[OSi(OtBu)3]2 (1) and
B[OSi(OtBu)3]3 (2), respectively. Compounds 1 and 2 are efficient single-source molecular precursors to B/Si/O
materials via thermolytic routes in nonpolar media, as demonstrated by the generation of BO1.5·2SiO2 (BOSi2xg)
and BO1.5·3SiO2 (BOSi3xg) xerogels, respectively. Use of a block copolymer template provided B/Si/O materials
(BOSi2epe and BOSi3epe) with a broad distribution of mesopores (by N2 porosimetry) and smaller, more uniform
particle sizes (by TEM) as compared to the nontemplated materials. Hydrolyses of 1 and 2 with excess H2O
resulted in formation of the expected amounts of tBuOH and HOSi(OtBu)3; however, reaction of 1 with 1 equiv of
H2O led to isolation of the new boronous acid HOB[OSi(OtBu)3]2 (3). This ligand precursor is well suited for the
synthesis of new metal (siloxy)boryloxide complexes via proton-transfer reactions involving the BOH group. The
reaction of 3 with Cp2ZrMe2 resulted in formation of Cp2Zr(Me)OB[OSi(OtBu)3]2 (4) in high yield. This rare example
of a transition metal boryloxide complex crystallizes in the triclinic space group P1̄ and exhibits a crystal structure
with an unprecedented number of independent molecules in its asymmetric unit (i.e., Z‘ = 18 and Z = 36). This
unusual crystal structure presented an opportunity to perform statistical analyses of the metric parameters for the
18 crystallographically independent molecules. Complex 4 readily converts to Cp2Zr[OSi(OtBu)3]2 (5) upon thermolysis
or upon dissolution in Et2O at room temperature.
%I ACS Publications