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Abstract The reaction of an aryne with an alkyne to generate a benzocyclobutadiene (BCB) intermediate is rare. We report here examples of this reaction, revealed by Diels–Alder trapping of the BCB by either pendant or external electron‐deficient alkynes. Mechanistic delineation of the reaction course is supported by DFT calculations. A three‐component process joining the benzyne first with an electron‐rich and then with an electron‐poor alkyne was uncovered. Reactions in which the BCB functions in a rarely observed role as a 4π diene component in Diels–Alder reactions are reported. The results also shed new light on aspects of the hexadehydro‐Diels–Alder reaction used to generate the benzynes.
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Palladium Nano-Dispersed and Stabilized in Organically Modified Silicate as a Heterogeneous Catalyst for the Conversion of Aldehydes into O-Silyl Ether Derivatives under Neat Conditions
Abstract Palladium nanoparticles are dispersed and stabilized in organically modified silicate (Pd@MTES), and characterized by a number of spectroscopic techniques, including FTIR, TEM, SEM, and XPS. The catalytic effect of this material toward the hydrosilylation of aldehydes and ketones is explored, and the scope of the reaction investigated, with 26 examples provided. This reaction proceeds under neat conditions via heterogeneous catalysis, and a mechanistic pathway supported by DFT calculations is proposed.
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- Award ID(s):
- 1954734
- PAR ID:
- 10517315
- Publisher / Repository:
- https://www.thieme-connect.com/products/ejournals/abstract/10.1055/a-2326-6277
- Date Published:
- Journal Name:
- Synthesis
- Volume:
- 56
- Issue:
- 13
- ISSN:
- 0039-7881
- Page Range / eLocation ID:
- 2031 to 2046
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1055/a-2326-6277
