Abstract Microwave (MW) heating is more effective than conventional (CONV) heating for promoting a high‐temperature oxidative cycloisomerization reaction that was previously reported as a key step in a total synthesis of the natural product illudinine. The thermal reaction pathway as envisioned is an inverse electron‐demand dehydro‐Diels–Alder reaction with in situ oxidation to generate a substituted isoquinoline, which itself is unstable to the reaction conditions. Observed reaction yields were higher at a measured bulk temperature of 200 °C than at 180 °C or 220 °C; at 24 hours than at earlier or later time points; and when the reaction solution was heated using MW energy as opposed to CONV heating with a metal heat block. Selective MW heating of polar solute aggregates is postulated to explain these observations.
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Electron Heating in Low-Mach-number Perpendicular Shocks. I. Heating Mechanism
- Award ID(s):
- 1716567
- PAR ID:
- 10063443
- Date Published:
- Journal Name:
- The Astrophysical Journal
- Volume:
- 851
- Issue:
- 2
- ISSN:
- 1538-4357
- Page Range / eLocation ID:
- 134
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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