## Abstract Ring polymers are synthesized using a cyclic bifunctional thioester as initiator for REP of thiiranes. PMT yields satisfactory results, whereas polymerization with MT appears to develop dead polymeric material as byβproduct and TBMT gives only negligible conversion rates. The process pr
Mechanism of the concerted ring expansion of singlet cyclopropyl nitrene
β Scribed by Huabin Sun; Chengbu Liu; Liming Zhao; Lu Deng
- Publisher
- Elsevier Science
- Year
- 1994
- Tongue
- English
- Weight
- 391 KB
- Volume
- 228
- Category
- Article
- ISSN
- 0009-2614
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β¦ Synopsis
The isomerization by concerted ring expanding of singlet cyclopropyl nitrene has been studied using the self-consistent field (SCF) method with the 3-21G basis set. The transition state has been obtained. The disrotation-conrotation mechanism has been proposed and discussed with the Woodward-Hoffmann approach. The barrier height for the ring expansion is 38.89 kJ/ mol and the released energy is 232.21 kJ/mol. The relative structure data are given.
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