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Bulky 2,6-disubstituted aryl siloxanes and a disilanamine.

ABSTRACT: The crystal structures of 5-bromo-1,3-di-tert-butyl-2-[(tri-methyl-sil-yl)-oxy]benzene, C17H29BrOSi, (I), 1,3-di-tert-butyl-2-[(tri-methyl-sil-yl)-oxy]benzene, C17H30OSi, (II), and N-(2,6-diiso-propyl-phen-yl)-1,1,1-trimethyl-N-(tri-methyl-sil-yl)silanamine, C18H35NSi2, (III), are reported. Compound (I) crystallizes in space group P21/c with Z' = 1, (II) in Pnma with Z' = 0.5 and (III) in Cmcm with Z' = 0.25. Consequently, the mol-ecules of (II) are constrained by m and those of (III) by m2m site symmetries. Despite this, both (I) and (II) are distorted towards mild boat conformations, as is typical of 2,6-di-tert-butyl-substituted phenyl compounds, reflecting the high local steric pressure of the flanking alkyl groups. Compound (III) by contrast is planar and symmetric, and this lack of distortion is compatible with the lower steric pressure of the flanking 2,6-diisopropyl substituents.

SUBMITTER: Marszaukowski F

PROVIDER: S-EPMC7057366 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Bulky 2,6-disubstituted aryl siloxanes and a disilanamine.

Marszaukowski Flavia F Wohnrath Karen K Boeré René T RT

Acta crystallographica. Section E, Crystallographic communications 20200206 Pt 3

The crystal structures of 5-bromo-1,3-di-tert-butyl-2-[(tri-methyl-sil-yl)-oxy]benzene, C17H29BrOSi, (I), 1,3-di-tert-butyl-2-[(tri-methyl-sil-yl)-oxy]benzene, C17H30OSi, (II), and N-(2,6-diiso-propyl-phen-yl)-1,1,1-trimethyl-N-(tri-methyl-sil-yl)silanamine, C18H35NSi2, (III), are reported. Compound (I) crystallizes in space group P21/c with Z' = 1, (II) in ...[more]

PMID: 32148868

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