Sigmatropic [1,3]-boron shift (permanent allylic rearrangement) in 3-allyl-3-borabicyclo[3.3.1]nonanes
- Authors
- Type
- Published Article
- Journal
- Russian Chemical Bulletin
- Publisher
- Springer US
- Publication Date
- Feb 01, 2014
- Volume
- 63
- Issue
- 2
- Pages
- 480–486
- Identifiers
- DOI: 10.1007/s11172-014-0456-3
- Source
- Springer Nature
- Keywords
- License
- Yellow
Abstract
2D 1H-1H EXSY NMR spectroscopy show that the free energy of activation ΔG≠ in six 3-allyl-3-borabicyclo[3.3.1]nonane derivatives is significantly higher (72–86 kJ mol−1) than that in typical allylboranes (48–66 kJ mol−1). For the first member of the series, viz., 3-allyl-3-borabicyclo[3.3.1]nonane, the activation parameters of the permanent allylic rearrangement were also determined (ΔH≠ = 82.7±3.4 kJ mol−1, ΔS≠ = −11.8±10.3 J mol−1 K−1, EA = 85.5±3.4 kJ mol−1, lnA = 29.2±1.2).