Configurational double bond selectivity in the epoxidation of hydroxy-terminated polybutadiene with m-chloroperbenzoic acid
✍ Scribed by Marcelo Aguiar; Sonia Cabral de Menezes; Leni Akcelrud
- Publisher
- John Wiley and Sons
- Year
- 1994
- Tongue
- English
- Weight
- 436 KB
- Volume
- 195
- Category
- Article
- ISSN
- 1022-1352
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
The selectivity of the three different double bonds (CIS, TRANS and VINYL) of hydroxyterminated polybutadiene regarding epoxidation was evaluated, using m‐chloroperbenzoic acid in toluene below room temperature (−10°C, −5°C, 0°C and 5°C). To determine the kinetic constants for the three configuratons (k~1,cis~ = (2,59–0,6) × 10^−2^ L · mol^−1^ · min^−1^; k~2, trans~ = (5,35–0,82) × 10^−2^ L · mol^−1^ · min^−1^; k~3, vinyl~ = (0,97–0,01) × 10^−2^ L · mol^−1^ min^−1^), ^1^H and ^13^C NMR was used along with a system of three parallel equations. The activation energy values were also evaluated (E~a, cis~ = 53,9 kJ · mol^−1^; E~a, trans~ = 70,7 kJ · mol^−1^ and E~a~, vinyl = 261,1 kJ · mol^−1^) for the three double bond types.