77 research outputs found
Selective Enzymatic Oxidation of Silanes to Silanols
Compared to the biological world's rich chemistry for functionalizing carbon, enzymatic transformations of the heavier homologue silicon are rare. We report that a wildâtype cytochrome P450 monooxygenase (P450_(BM3) from Bacillus megaterium, CYP102A1) has promiscuous activity for oxidation of hydrosilanes to give silanols. Directed evolution was applied to enhance this nonânative activity and create a highly efficient catalyst for selective silane oxidation under mild conditions with oxygen as the terminal oxidant. The evolved enzyme leaves CâH bonds present in the silane substrates untouched, and this biotransformation does not lead to disiloxane formation, a common problem in silanol syntheses. Computational studies reveal that catalysis proceeds through hydrogen atom abstraction followed by radical rebound, as observed in the native CâH hydroxylation mechanism of the P450 enzyme. This enzymatic silane oxidation extends nature's impressive catalytic repertoire
EPR spectra of radical-adducts of methyldichlorosilyl radicals with a perfluoro-N-acylimine and perfluoro-?-lactam
SingleâElectron Transfer Reactions in Frustrated and Conventional Silylium Ion/Phosphane Lewis Pairs
Epr study of tertiary cyclic perfluorinated radicals: Methylcyclopentyl and decalyl radicals
Trifluoromethylation of [60]- and [70]Fullerene in the Ionization Chamber of a Mass Spectrometer
Stable radicals ? The intermediates in the photochemical chlorination of unsaturated perfluoro compounds
Epr investigation of the adducts of element-centered radicals with polyhedral carbon clusters (fullerenes)
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