81236-83-1Relevant academic research and scientific papers
Synthesis and reactivity of α-lithio α-trimethylsilyl cyclopropanes and related derivatives
Halazy,Dumont,Krief
, p. 4737 - 4740 (1981)
α-lithio α-trimethylsilyl cyclopropanes have been prepared by two different routes. They have been tested as precursors of alkylidene cyclopropanes, cyclopropylidienes and α-silyl α-vinyl cyclopropanes.
The 1-(trimethylsilyl)bicyclobutonium ion: NMR spectroscopy, isotope effects, and quantum chemical ab initio calculations of a new hypercoordinated carbocation
Siehl, Hans-Ullrich,Fuss, Martin,Gauss, Jürgen
, p. 5983 - 5991 (1995)
The 1-(trimethylsilyl)bicyclobutonium ion is generated from (1′-(trimethylsilyl)cyclopropyl)methanol by reaction with SbF5. The NMR spectroscopic data in SO2ClF/SO2F2 solution at -128°C are in accord with a bridged puckered bicyclobutonium structure undergoing a 3-fold rapid degenerate rearrangement that renders the two β- and one γ-methylene groups equivalent, leading to one averaged 13C-NMR signal for the CH2 groups at 48.9 ppm. Conformational ring inversion is slow so that two separate signals for the three averaged endo-CH2 (4.04 ppm) and three averaged exo-CH2 hydrogens (3.24 ppm) are observed. The deuterium equilibrium isotope effects for exo- and endo-CHD-labeled cations are different in sign and magnitude and are rationalized by different endo- and exo-C-H bond force constants at the pentacoordinated carbon. NMR chemical shift calculations for the 1-silylbicyclobutonium ion and the (1′-silylcyclopropyl)methyl cation were performed with the GIAO-SCF and GIAO-MP2 methods. The experimental shifts are satisfactorily reproduced by GIAO-MP2//tzp/dz calculated shifts for the 1-silylbicyclobutonium structure. The good agreement between theory and experiment supports a fully degenerate set of interconverting 1-(trimethylsilyl)bicyclobutonium ions and excludes contributions from other isomers to the observed equilibrium process. The geometric and electronic properties of the 1-(trimethylsilyl)bicyclobutonium cation are intermediate between those of the parent bicyclobutonium ion and those of the methyl-substituted analogue.
Synthesizing Molecules with Linear Tricyclic 5/5/5 and 6/5/5 Skeletons via [5 + 2 + 1]/Ene Strategy
Liu, Jing,Zhou, Yi,Zhu, Jiaqi,Yu, Zhi-Xiang
supporting information, p. 7566 - 7570 (2021/10/02)
Report here is the development of a [5 + 2 + 1]/ene strategy for the synthesis of molecules with linear tricyclic 5/5/5 and 6/5/5 skeletons widely found in natural products. The first step of this strategy is applying a Rh-catalyzed [5 + 2 + 1] reaction o
Silicon in Organic Synthesis. 24. Preparation and Selected Reactions of Functionalized 1-(Trimethylsilyl)-Substituted Cyclopropanes
Wells, Gregory J.,Yan, Tu-Hsin,Paquette, Leo A.
, p. 3604 - 3609 (2007/10/02)
Several methods for preparing bifunctional 1-(trimethylsilyl)-substituted cyclopropanes are described.The methyl bromide 4, available by Simmons-Smith cyclopropanation of 2 and bromination with phosphorus tribromide, is shown to be highly reactive to SN2 displacement and therefore easily transformed into a variety of other derivatives including the phenyl sulfide, phenyl sulfone, nitrile, and phenyl selenide.Ring-closure protocols have been applied to gain access to the triphenylphosphonium salt, phosphonate ester, and carboxaldehyde (22).The dimethyl acetal 23 ofthis aldehyde gives every indication of being an excellent conjunctive reagent as exemplified by its conversion to 24, 26, and 30.Reactive anions of type A (X = SO2Ph, SPh, SePh, CN) have been generated and in certain cases utilized for additional chemical transformations.
SILICON IN ORGANIC SYNTHESIS. 16. A SHORT SYNTHESIS OF (+/-)-α-VETISPIRENE
Yan, Tu-Hsin,Paquette, Leo A.
, p. 3227 - 3230 (2007/10/02)
α-Vetispirene, a prototypical spirobicyclic sesquiterpene, has been prepared in an efficient five-step reaction sequence beginning with α-trimethylsilyl cyclopropanecarboxaldehyde.A new desiliconative alkylation is featured.
