An efficient synthesis of dihydro-isoquinolines via a Pd–catalyzed double C–H bond activation/annulation featuring a short reaction time, high atom economy and the formation of a sterically less favoured tertiary C–N bond.
Intrinsic deuterium isotope effects of deuteriatedtert-butyl groups on the13C NMR spectra of aromatic compounds
作者:Hartmut H. Balzer、Stefan Berger
DOI:10.1002/mrc.1260280511
日期:1990.5
The 3Δ‐deuteriumisotopeeffects of partially and fully deuteriated tert‐butyl groups on the 13C NMRspectra of tert‐butylbenzene and derivatives are discussed in detail. It is shown that they correlate with the chemical shift of C‐1 of the aromatic ring. It has been demonstrated that when deuterium is replaced with some other substituents, the SCS values of these substituents show a parallel behaviour
Deuterium isotope studies of the dehydration alcohols by reaction with triphenylphosphine-tetrachloromethane
作者:Hossein A. Dabbagh、Boris Franzus、Thomas T.-S. Huang、Burtron H. Davis
DOI:10.1016/s0040-4020(01)80935-2
日期:1991.1
(2M2P) (85–95%) but substitution (of OH by Cl) was dominant for 2-butanol (75–95%). Deuterium retention in the butenes from the conversion of (EB) indicated that 98% or more of the dehydration followed an anti-elimination pathway, and there was a preference for Saytzeff elimination. An isotope effect for deuterium elimination (kH/kD) for the alkene-forming step for (EB) and (HDMP) was about 2.0, and
2-丁醇,2-丁醇-2d 1,赤型-2-丁醇-3d 1,(EB),2-甲基-2-丙醇(2M2P)和1,1,1,3,3,3的反应-hexadeuterio-2-methyl-2-propanol(HDMP)分别具有CCl 4和Ph 3研究了在36–85°C温度范围内的极性或非极性溶剂中的P。对于2-丁醇,脱水产物的分数随温度升高而增加;(2M2P)观察到相反的温度效应。脱水是(2M2P)(85-95%)的主要途径,但2-丁醇(75-95%)的取代(OH被Cl取代)是主要的途径。(EB)的转化使丁烯中的氘保留,表明98%或更多的脱水遵循抗消除途径,因此优先考虑Saytzeff消除。(EB)和(HDMP)的烯烃形成步骤的氘消除同位素效应(k H / k D)约为2.0,并且温度和溶剂极性均未对(k H k D)产生影响)在调查范围内。出乎意料的是,对于(EB)而不是(HDMP)形成卤代烷的相对速率存在同位素效应。
Kinetics and mechanism of dealkylation of coordinated isocyanide in Fe(PMe<sub>3</sub>)<sub>2</sub>(<i>t</i>-BuNC)<sub>3</sub>
作者:Christine L Tennent、William D Jones
DOI:10.1139/v05-023
日期:2005.6.1
were found to be moderately thermally stable at room temperature. Stability was found to decrease in the sequence 2,6-xylyl > Ph > CH2CMe3 > t -Bu >M e >> i-Pr > Et. The reaction of the isocyanides where R = i-Pr and Et did not give an isolable crystalline product. The complex Fe(PMe3)2(t-BuNC)3 could be isolated as a yellow crystal- line solid, but was found to decompose at 25 °C over several days
零价铁络合物 Fe(PMe3)2(t-BuNC)3 经历 CN 键的热裂解,得到 Fe(PMe3)2(t-BuNC)2(H)(CN) 和异丁烯。该反应遵循一级动力学,氢原子供体 1,4- 环己二烯的加入导致优先形成异丁烷而不是异丁烯。机理研究与决定 C-N 键均裂的速率一致,产生叔丁基自由基。使用了几种异氰化物,发现所有得到的复合物都对空气非常敏感。发现大多数配合物在室温下具有适度的热稳定性。发现稳定性降低的顺序为 2,6-二甲苯基 > Ph > CH2CMe3 > t -Bu >Me >> i-Pr > Et。R = i-Pr 和 Et 的异氰化物的反应没有产生可分离的结晶产物。复合物 Fe(PMe3)2(t-BuNC)3 可以分离为黄色结晶固体,但发现在 25 °C 下会分解几天。所有这些配合物都具有相似的 1 H NMR 光谱,其中三个等效异氰化物配体的共振以及两个等效三甲基膦配体的假三重峰