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Abstract Reactions of (O=)PH(OCH2CH3)2and BrMg(CH2)mCH=CH2(4.9–3.2 equiv;m=4 (a), 5 (b), 6 (c)) give the dialkylphosphine oxides (O=)PH[(CH2)mCH=CH2]2(2 a–c; 77–81 % after workup), which are treated with NaH and then α,ω‐dibromides Br(CH2)nBr (0.49–0.32 equiv;n=8 (a′), 10 (b′), 12 (c′), 14 (d′)) to yield the bis(trialkylphosphine oxides) [H2C=CH(CH2)m]2P(=O)(CH2)n(O=)P[(CH2)mCH=CH2]2(3 ab′,3 bc′,3 cd′,3 ca′; 79–84 %). Reactions of3 bc′and3 ca′with Grubbs’ first‐generation catalyst and then H2/PtO2afford the dibridgehead diphosphine dioxides(4 bc′,4 ca′; 14–19 %,n′=2m+2);31P NMR spectra show two stereoisomeric species (ca. 70:30). Crystal structures of two isomers of the latter are obtained,out,out‐4 ca′and a conformer ofin,out‐4 ca′that features crossed chains, such that the (O=)P vectors appearout,out. Whereas4 bc′resists crystallization, a byproduct derived from an alternative metathesis mode, (CH2)12P(=O)(CH2)12(O=)P(CH2)12, as well as3 ab′and3 bc′, are structurally characterized. The efficiencies of other routes to dibridgehead diphosphorus compounds are compared.
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This content will become publicly available on May 2, 2026
Optimizing active sites via chemical bonding of 2D metal–organic frameworks and MXenes for efficient hydrogen evolution reaction activity
A conductive MXene (Ti3C2Tx) integrated with 2D Ni3(HITP)2-MOFvia in situsynthesis enhances active site exposure, boosting electrocatalytic HER performance for efficient, sustainable hydrogen production.
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- Award ID(s):
- 1945218
- PAR ID:
- 10614551
- Publisher / Repository:
- Nanoscale
- Date Published:
- Journal Name:
- Nanoscale
- Volume:
- 17
- Issue:
- 17
- ISSN:
- 2040-3364
- Page Range / eLocation ID:
- 11028 to 11036
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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