A variety of substituted furans a-6J undergo the intramolecular Die&Alder reaction at high pressure (12.5 kbar) to provide oxatricyclo adducts Q-12) within 24 hours at room temperature.
Reactions at high pressure, part 10: the volume profile of an intramolecular diels-alder reaction
β Scribed by Neil S. Isaacs; Paul Van der Beeke
- Publisher
- Elsevier Science
- Year
- 1982
- Tongue
- French
- Weight
- 109 KB
- Volume
- 23
- Category
- Article
- ISSN
- 0040-4039
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β¦ Synopsis
the intramolecular cyclisation of furans, 3, proceeds with the following activation characteristics: J(R=Et) has EA= 72.5, H=69. 9 kJmo1 -' s" ,62Jf1 , mol-l, d= -25 cm3mol-'.
The results confirm the existence of a negative volume contribution from the approach of reagents in intermolecular analogues.
Many examples of intramolecular Diels-Alder reactions are now known 1 and are the sources of W. J. LeNoble,
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