Dioxaborolane, 2- Dimethylphenylsilyl

The diisopropyl 2-dimethylphenylsilyl-2-propenyl- and 2-[cyclohexyloxy(dimethyl)silyl]-l,3,2-dioxaborolane-4,5-dicarboxylate reagents 7 and 8 were recently introduced for the enantiose-lective a- and y-hydroxyallylation of aldehydes86. 

Dimethylphenylsilyl)-4,4,5,5-tetramethyl-l,3,2-dioxaborolane (1) is prepared by reaction of dimethylphenylsilyllithium with 4,4,5,5-tetramethyl-l,3,2-dioxaborolane (pinacolborane, 2equiv) or 2-isopropoxy-4,4,5,5-tetramethyl-l,3,2-dioxaborolane (2 equiv) (eq 1). Silylboronic esters 2 and 3a are also synthesized via similar routes using methyldiphenylsilyllithium and [(diethyl-ainino)diphenylsilyl]lithium, respectively (eq 2). Diethylamino-substituted silylborane 3a is converted to a chlorine-substituted 4a by reaction with dry hydrogen chloride (eq 3). Silylborane 1 is... 

Article previously published in the electronic Encyclopedia of Reagents for Orgenic Synthesis as 2-(Dimethylphenylsilyl)-4,4,5,5-tetramethyl-l,3,2-dioxaborolane. DOI 10.1002/047084289X. m01328. 

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