Orientation in the chlorination and bromination of phenylsilanes containing SiF3 and Si(CH3)3 groups

New Silicon Groups as Potential Chiral Auxiliaries. Synthesis and Highly Selective Chiral 1,6-Induction in 1,2-Additions to Acylsilanes

“…Several methods described in the literature to replace an aryl group at silicon (actually designed for the opposite purpose, namely to replace a silicon group at an aromatic system) − proved not applicable for our substrate. A modification of the bromination protocol of Ponomarenko was finally successful: treatment of 9 in the presence of a catalytic amount of Fe with 1.2 equiv of Br 2 in 1,2-dichloroethane at −30 °C, instead of using Br 2 at 50 °C as the solvent, delivered a highly reactive and moisture-sensitive bromosilane that was immediately reduced with LiAlH 4 to form hydrosilane 10 (91% yield over the two steps). This compound was readily purified by chromatography and can be kept on stock at 4 °C for a prolonged period of time without change.…”

Desilatranation of 1-organylsilatranes

“…1 H NMR spectrum (DMSO-d 6 ), δ, ppm: 2.92 t (6Н, NCH 2 , 3 J 5.9 Hz), 3.68 t (6Н, ОСН 2 ). 13 Reaction of phenyltrifluorosilane with 1-ethoxysilatrane (2) was performed similarly, yield of silatrane 3 0.41 g (75%).…”

“…1 H, 13 C, 29 Si, and 19 F were registered on a spectrometer Bruker DРХ-400 (400.13, 100.61, 79.50, and 376.50 МHz respectively) at 297 K. The elemental analysis was carried out on an automatic CHNS-analyzer Thermo Scientific Flash 2000. The fluorine content was determined by titrimetric Schöniger method [12].…”

“…Initial silatranes 1, 2, and 4-6 were prepared as described before [8]. Phenyltrifluorosilane was synthesized by Szwarc reaction along a published method [13].…”