NMR spectroscopy of organolithium compounds, Part XVI
摘要:
The aggregation behaviour of butyllithium (BuLi), phenyllithium (PhLi), and lithium diisopropylamide (LDA) in dimethoxy- and diethoxymethane (methylal and ethylal, respectively) has been studied by NMR spectroscopy using the isotopic fingerprint method and C-13,Li-6 as well as N-15,Li-6 spin-spin coupling constants. In both solvents, LDA exists as a dimer. while BuLi forms a tetramer. PhLi forms a dimer in methylal, whereas two major aggregates exist in ethylal. Due to solvent viscosity at lower temperatures, their structure could not be determined.
Large concentration effects on the magnitude of secondary alpha-deuterium kinetic isotope effects
作者:Kenneth Charles Westaway、Zbigniew Waszczylo、Peter James Smith、Kanchugarakoppal S. Rangappa
DOI:10.1016/s0040-4039(00)98456-9
日期:1985.1
Because the secondary alpha-deuterium kineticisotopeeffects in some SN2 and E2 reactions are strongly concentration dependent, isotopeeffects measured at a single concentration could lead to erroneous conclusions about the mechanisms and transition state structures.
由于某些S N 2和E2反应中的次级α-氘动力学同位素效应强烈依赖于浓度,因此在单一浓度下测量的同位素效应可能导致有关机理和过渡态结构的错误结论。
Westaway, Kenneth Charles; Lai, Zhu-gen, Canadian Journal of Chemistry, 1988, vol. 66, p. 1263 - 1271
作者:Westaway, Kenneth Charles、Lai, Zhu-gen
DOI:——
日期:——
Fang, Yao-Ren; Westaway, Kenneth Charles, Canadian Journal of Chemistry, 1991, vol. 69, # 6, p. 1017 - 1021