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Title: Borane-Catalyzed Selective Hydrosilylation of Internal Ynamides Leading to β-Silyl ( Z )-Enamides

Authors:
; ; ORCiD logo
Publication Date:
Research Org.:
Energy Frontier Research Centers (EFRC) (United States). Center for Catalytic Hydrocarbon Functionalization (CCHF)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1397174
DOE Contract Number:
SC0001298
Resource Type:
Journal Article
Resource Relation:
Journal Name: Organic Letters; Journal Volume: 19; Journal Issue: 1; Related Information: CCHF partners with University of Virginia (lead); Brigham Young University; California Institute of Technology; Colorado School of Mines; University of Maryland; University of North Carolina, Chapel Hill; University of North Texas; Princeton University; The Scripps Research Institute; Yale University
Country of Publication:
United States
Language:
English

Citation Formats

Kim, Youngchan, Dateer, Ramesh B., and Chang, Sukbok. Borane-Catalyzed Selective Hydrosilylation of Internal Ynamides Leading to β-Silyl ( Z )-Enamides. United States: N. p., 2017. Web. doi:10.1021/acs.orglett.6b03485.
Kim, Youngchan, Dateer, Ramesh B., & Chang, Sukbok. Borane-Catalyzed Selective Hydrosilylation of Internal Ynamides Leading to β-Silyl ( Z )-Enamides. United States. doi:10.1021/acs.orglett.6b03485.
Kim, Youngchan, Dateer, Ramesh B., and Chang, Sukbok. Fri . "Borane-Catalyzed Selective Hydrosilylation of Internal Ynamides Leading to β-Silyl ( Z )-Enamides". United States. doi:10.1021/acs.orglett.6b03485.
@article{osti_1397174,
title = {Borane-Catalyzed Selective Hydrosilylation of Internal Ynamides Leading to β-Silyl ( Z )-Enamides},
author = {Kim, Youngchan and Dateer, Ramesh B. and Chang, Sukbok},
abstractNote = {},
doi = {10.1021/acs.orglett.6b03485},
journal = {Organic Letters},
number = 1,
volume = 19,
place = {United States},
year = {Fri Jan 06 00:00:00 EST 2017},
month = {Fri Jan 06 00:00:00 EST 2017}
}
  • SiAlON ceramics, solid solutions based on the Si 3N 4 structure, are important, lightweight structural materials with intrinsically high strength, high hardness, and high thermal and chemical stability. Described by the chemical formula β-Si 6–zAl zO zN 8–z, from a compositional viewpoint, these materials can be regarded as solid solutions between Si 3N 4 and Al 3O 3N. A key aspect of the structural evolution with increasing Al and O (z in the formula) is to understand how these elements are distributed on the β-Si 3N 4 framework. The average and local structural evolution of highly phase-pure samples of β-Simore » 6–zAl zO zN 8–z with z = 0.050, 0.075, and 0.125 are studied here, using a combination of X-ray diffraction, NMR studies, and density functional theory calculations. Synchrotron X-ray diffraction establishes sample purity and indicates subtle changes in the average structure with increasing Al content in these compounds. Solid-state magic-angle-spinning 27Al NMR experiments, coupled with detailed ab initio calculations of NMR spectra of Al in different AlO qN 4–q tetrahedra (0 ≤ q ≤ 4), reveal a tendency of Al and O to cluster in these materials. Independently, the calculations suggest an energetic preference for Al–O bond formation, instead of a random distribution, in the β-SiAlON system.« less
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