Neuartige Silane mit sterisch anspruchsvollen Aryl‐Substituenten

Novel Silanes with Sterically Demanding Aryl Substituents A series of novel m ‐terphenylsilanes was synthesized and fully characterized. Halogenation of Si(C 6 H 3 ‐2,6‐Trip 2 )H 3 ( 1 , Trip = C 6 H 2 ‐2,4,6‐ i Pr 3 ) with ICl and BI 3 afforded the m ‐terphenylmonochlorosilane Si(C 6 H 3 ‐2,6‐Trip 2 )H 2 Cl ( 2 ) and the m ‐terphenyldiiodosilane Si(C 6 H 3 ‐2,6‐Trip 2 )HI 2 ( 3 ), respectively. The chiral phosphanylmethylsilane Si(C 6 H 3 ‐2,6‐Trip 2 )HCl(CH 2 PMe 2 ) ( 6 ) was obtained by metathetical exchange of Si(C 6 H 3 ‐2,6‐Trip 2 )HCl 2 ( 4 ) with the Grignard reagent Me 2 PCH 2 MgCl ( 5 ). Similarly, metathetical exchange of SiBr 4 with 0.5 equiv. of {Li(C 6 H 3 ‐2,6‐Mes)} 2 ( 7 ) yielded the m ‐terphenyltribromsilane Si(C 6 H 3 ‐2,6‐Mes 2 )Br 3 ( 8 ). A Pd(II) catalyzed reaction of MesSiH 3 ( 10 ) with 2‐iodopropane afforded the triiodosilane MesSiI 3 ( 11 ) bearing the sterically less demanding mesityl substituent. The silanes were fully characterized and the molecular structures of compounds 2 and 11 were determined by single‐crystal X‐ray diffraction.