Publications by authors named "Robert B Yelle"

Aldehyde- and ketone-derived cyanohydrins were reacted with the nitrile hydration catalysts [PtCl(PR(2)OH){(PR(2)O)(2)H}] (1) and Cp(2)Mo(OH)(OH(2))(+) (2) under a variety of hydration reaction conditions. In general, the cyanohydrins were hydrated to the amides rather slowly using these catalysts, but no subsequent hydrolysis of the amide products occurred. Catalyst 2 was much less reactive than catalyst 1, showing at best trace amounts of amide product.

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Electronic structure calculations using density functional theory were performed on potential intermediates in the reaction of Fe(dmpe)(2)N(2) (dmpe = 1,2-bis(dimethylphosphino)ethane) with protons. Three mechanisms were investigated and compared, and the possibility of a two-electron reduction by a sacrificial Fe(dmpe)(2)N(2) complex was considered in each mechanism. A Chatt-like mechanism, involving the stepwise addition of protons to the terminal nitrogen, was found to be the least favorable.

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A series of 12 thieno-fused macrocycles based on the dehydro[14]annulene framework have been prepared. Studies have focused on the optical and electronic properties of the dehydrobenzothieno[14]annulenes (DBTAs) and dehydrothieno[14]annulenes (DTAs) utilizing NMR spectroscopy, UV-vis spectrophotometry, electrochemistry, and DFT computations. X-ray crystal structures were also obtained for two of the macrocycles.

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The protein matrix of an electron transfer protein creates an electrostatic environment for its redox site, which influences its electron transfer properties. Our studies of Fe-S proteins indicate that the protein is highly polarized around the redox site. Here, measures of deviations of the environmental electrostatic potential from a simple linear dielectric polarization response to the magnitude of the charge are proposed.

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