Application of vinyl tris(trimethylsilyl)germanes in Pd-catalyzed couplings.
نویسندگان
چکیده
The oxidative treatment of vinyltris(trimethylsilyl)germanes with hydrogen peroxide (NaOH/H(2)O/THF) or tert-butyl peroxide (KH/THF) generates reactive germanol or germanoxane species that undergo Pd-catalyzed cross-couplings with aryl and alkenyl halides and aryl triflates in the presence of Pd(PPh(3))(4). Vinylgermanes having either a conjugated or isolated double bond serve as versatile transmetalation reagents. The E-germanes undergo coupling with retention of stereochemistry under aqueous and anhydrous conditions, while coupling of Z-germanes occurs with less stereoselectivity to produce a mixture of E/Z products.
منابع مشابه
Radical-mediated silyl- and germyldesulfonylation of vinyl and (alpha-fluoro)vinyl sulfones: application of tris(trimethylsilyl)silanes and tris(trimethylsilyl)germanes in Pd-catalyzed couplings.
[reaction: see text] Radical-mediated silyl- and germyldesulfonylations of various vinyl and (alpha-fluoro)vinyl sulfones with tris(trimethylsilyl)silane and germanium hydrides provide access to vinyl and (alpha-fluoro)vinyl silanes and germanes. Upon oxidative treatment with hydrogen peroxide in basic aqueous solution, the vinyl tris(trimethylsilyl)silanes and -germanes undergo Pd-catalyzed cr...
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ورودعنوان ژورنال:
- The Journal of organic chemistry
دوره 70 8 شماره
صفحات -
تاریخ انتشار 2005