The Diels–Alder reactivity of 5‐membered dienes is tunable through spirocyclization at the saturated center. As the size of the spirocycle decreases, the Diels–Alder reactivity increases with the cyclobutane spirocycle, spiro[3.4]octa‐5,7‐diene, being the most reactive. Density functional theory calculations suggest that spiro[3.4]octa‐5,7‐diene dimerizes 220,000‐fold faster than 5,5‐dimethylcyclopentadiene and undergoes a Diels–Alder reaction with ethylene 1200‐fold faster than 5,5‐dimethylcyclopentadiene. These findings show that spirocyclization is an effective way to enhance the Diels–Alder reactivity of geminally substituted 5‐membered dienes.
Catalytic generation of ortho -quinone dimethides via donor/donor rhodium carbenes
Substrates engineered to undergo a 1,4-C–H insertion to yield benzocyclobutenes resulted in a novel elimination reaction to yield
- Award ID(s):
- 2154083
- PAR ID:
- 10503368
- Publisher / Repository:
- RSC
- Date Published:
- Journal Name:
- Chemical Science
- Volume:
- 14
- Issue:
- 23
- ISSN:
- 2041-6520
- Page Range / eLocation ID:
- 6443 to 6448
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/d3sc00734k
