1530-32-1Relevant articles and documents
CATALYTIC PHOSPHORYLATION OF POLYFLUOROALKANOLS. 13. SOME AMMONIUM AND PHOSPHONIUM SALTS AS PHOSPHYRYLATION CATALYSTS
Kabachnik, M. I.,Zakharov, L. S.,Kudryatsev, I. Yu.
, p. 2553 - 2556 (1989)
It was shown that it is possible to use a series of ammonium and phosphonium salts as effective catalysts for the preparative synthesis of tris(polyfluoroalkyl)phosphates.The effect of the structure of substituted ammonium salts on their catalytic activity was studied in the phosphorylation of 1,1-dihydroperfluorobutanol by phosphorus oxychloride.It was determined that the reaction rate is effected not only by the solubility of the salt, but also by the nature of the ion pair and the steric access of the onium center for solvation by phosphoryl compounds.
Nucleophilic 1,1-Difluoroethylation with Fluorinated Phosphonium Salt
Deng, Zuyong,Liu, Can,Zeng, Xian-Liang,Lin, Jin-Hong,Xiao, Ji-Chang
, p. 12084 - 12090 (2016)
The fluorinated phosphonium salt (Ph3P+CF2CH3 BF4-) was shown to act as a nucleophilic 1,1-difluoroethylation agent to enable difluoroethylation of aldehydes and imines.
Conformational Control of Initiation Rate in Hoveyda-Grubbs Precatalysts
Gregg, Zackary R.,Griffiths, Justin R.,Diver, Steven T.
, p. 1526 - 1533 (2018)
When the coordinating isopropyl ether of the Hoveyda precatalyst is replaced by a cyclohexyl ether, it is possible to control the substituent's conformation in either the equatorial or axial position. A stereodivergent synthesis of axial and equatorial cyclohexyl vinyl ethers provided access to new ruthenium metathesis precatalysts by carbene exchange. The conformational disposition of the coordinating aryl ether was found to have a significant effect on the reactivity of the precatalyst in alkene metathesis. The synthesis of four new Ru carbene complexes is reported, featuring either the 1,3-bis(2,4,6-trimethylphenyl)dihydroimidazolylidene (H2IMes) or the 1,3-bis(2,6-diisopropylphenyl)dihydroimidazolylidene (SIPr) N-heterocyclic carbene ligand. The conformational isomers in the SIPr series were structurally characterized. Performance testing of all new precatalysts in three different ring-closing metatheses and an alkene cross metathesis illustrated superior performance by the precatalysts bearing axial coordinating ethers. Initiation rates with butyl vinyl ether were also measured, providing a useful comparison to existing Hoveyda-type metathesis precatalysts. Use of conformational control of the coordinating ether substituent provides a new way to modulate reactivity in this important class of alkene metathesis precatalysts.
Progress toward a Convergent, Asymmetric Synthesis of Jervine
De Jesús Cruz, Pedro,Johnson, Jeffrey S.,Zavesky, Blane P.
supporting information, (2020/04/30)
Progress toward a convergent approach for the enantioselective synthesis of the Veratrum alkaloid jervine is presented. The two requisite fragments were stereoselectively and efficiently fashioned from economical and readily available reagents. Key reactions include (a) a highly diastereoselective Ireland-Claisen rearrangement to establish the necessary cis-relationship between the amine and methyl group on the tetrahydrofuran E-ring; (b) a diastereoselective selenoetherification reaction that enabled the assembly of the D/E oxaspiro[4.5]decene in the needed configuration; and (c) an enzymatic desymmetrization of an abundant achiral diol en route to a key four-carbon building block as a practical alternative to a protected Roche ester reduction.
Visible Light Induced Cyclization to Spirobi[indene] Skeletons from Functionalized Alkylidienecyclopropanes
Li, Quanzhe,Liu, Jiaxin,Shi, Min,Wei, Yin
supporting information, (2020/03/26)
In this paper, we revealed a metal-free and visible light photoinduced method for the rapid construction of spirobi[indene] skeletons, providing a simple and efficient way for easy access to spirobi[indene] scaffolds under mild conditions along with a broad substrate scope and good functional group tolerance.
