We report a Rh-catalyzed, enantioselective silylation of arene C–H bonds directed by a (hydrido)silyl group. (Hydrido)silyl ethers that are formed in situ by hydrosilylation of benzophenone or its derivatives undergo asymmetric C–H silylation in high yield with excellent enantioselectivity in the presence of [Rh(cod)Cl]2 and a chiral bisphosphine ligand. The stereoselectivity of this process also allows enantioenriched diarylmethanols to react with site selectivity at one aryl group over the other. Enantioenriched benzoxasiloles from the silylation process undergo a range of transformations to form C–C, C–O, C–I, or C–Br bonds.

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The cross section for the bremsstrahlung resulting from high-energy collisions of electrons with protons is calculated, considering the electrons as extreme relativistic and taking into consideration the proton's recoil, anomalous magnetic moment, bremsstrahlung, and form factors. The final cross section is integrated over the recoil proton and final photon to obtain a formula of interest for the Stanford accelerator experiments. The computation of the integrated cross section, made without regard for radiative corrections and mesonic contributions, is estimated to be accurate to 2% in the energy ranges of interest. This cross section is corrected for radiative effects, which produce an additional uncertainty of less than 5% and possibly as little as 1%. Resonance effects due to meson interactions in the "virtual Compton effect" diagrams, however, become significant in the range of interest. Their contribution to the cross section is discussed.