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The synthesis of chiral organosilicon compounds is highly appealing due to their wide and important applications in synthetic chemistry and medicinal science. However, catalytic asymmetric disilylation are surprisingly underrepresented because of the lack of enantioselective methods in the stereoselective control of silyl group transformations. Herein, an asymmetric palladium‐catalyzed disilylation of ether‐tethered aryl iodide contained a styrene moiety through Heck/C−H activation sequence was explored for the first time. Upon high‐throughput screening of TADDOL‐derived phosphoramidites, it was found that L18 is a good match in combination with Pd(dtbpf)Cl2 in the tandem Heck/C−H activation of aryl iodide with hexamethyldisilane to afford disilylated 2.3‐dihydrobenzofunan derivatives in good yields with moderate enantioselectivity. [ABSTRACT FROM AUTHOR]

A novel and unusual palladium‐catalyzed [4+2] annulation of cyclopropenes with benzosilacyclobutanes is reported. This reaction occurred through chemoselective Si−C(sp2) bond activation in synergy with ring expansion/insertion of cyclopropenes to form new C(sp2)−C(sp3) and Si−C(sp3) bonds. An array of previously elusive bicyclic skeleton with high strain, silabicyclo[4.1.0]heptanes, were formed in good yields with excellent diastereoselectivity under mild conditions. An asymmetric version of the reaction with a chiral phosphoramidite ligand furnished a variety of chiral bicyclic silaheterocycle derivatives with good enantioselectivity (up to 95.5:4.5 er). Owing to the mild reaction conditions, the good stereoselectivity profile, and the ready availability of the functionalized precursors, this process constitutes a useful and straightforward strategy for the synthesis of densely functionalized silacycles. [ABSTRACT FROM AUTHOR]