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We report a low-temperature colloidal synthesis of WSe2nanocrystals from tungsten hexacarbonyl and diphenyl diselenide in trioctylphosphine oxide (TOPO). We identify TOPO-substituted intermediates, W(CO)5TOPO andcis-W(CO)4(TOPO)2by infrared spectroscopy. To confirm these assignments, we synthesize aryl analogues of phosphine-oxide-substituted intermediates, W(CO)5TPPO (synthesized previously, TPPO = triphenylphosphine oxide) andcis-W(CO)4(TPPO)2andfac-W(CO)3(TPPO)3(new structures reported herein). Ligation of the tungsten carbonyl by either the alkyl or aryl phosphine oxides results in facile labilization of the remaining CO, enabling low-temperature decomposition to nucleate WSe2nanocrystals. The reactivity in phosphine oxides is contrasted with syntheses containing phosphine ligands, where substitution results in decreased CO labilization and higher temperatures are required to induce nanocrystal nucleation.
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This content will become publicly available on March 26, 2026
Access to arynes from arenes via net dehydrogenation: scope, synthetic applications and mechanistic analysis
Arynes are versatile intermediates for organic synthesis and now they can be accessed from arenes in one or two-pot sequencesviaaryl thianthrenium (in situ) and aryl iodonium (isolated) intermediates, respectively.
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- Award ID(s):
- 2247802
- PAR ID:
- 10608468
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Chemical Science
- Volume:
- 16
- Issue:
- 13
- ISSN:
- 2041-6520
- Page Range / eLocation ID:
- 5547 to 5558
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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