Stereocontrolled Formation of Styrenes by Pd(0)-catalyzed Cross-coupling of Photoactivated (E)-Alkenylgermanes with Aryl Bromides
نویسندگان
چکیده
The stereocontrolled synthesis of (E)-configured styrenes via Pd(0)-catalyzed cross-couping of (E)-alkenylgermanes with aryl bromides is described. The germanes employed have bis(naphthalen-2-ylmethyl) substitution to allow photooxidative activation toward coupling and a C8F17-fluorous tag to facilitate purification by fluorous solid-phase extraction (F-SPE). The selectivities obtained suggest that a germyl-Stille rather than Heck-type mechanism predominates in the coupling step.
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