Cyclopropanation of olefins with a stable, iron-containing methylene transfer reagent

Brandt, Steven; Helquist, Paul

doi:10.1021/ja00515a074

Cited by 68 publications

(10 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In contrast, addition of trimethylsilyl triflate (TMS-OTf) to complex (4) gave a color change within minutes and the 19 . Given that this new carbene is cationic it is assumed that it will be strongly electrophilic unlike previous examples that our group has reported [49][50][51].…”

Section: Reactivitymentioning

confidence: 82%

Synthesis and Reactivity of Mn–CF3 Complexes

et al. 2019

View full text Add to dashboard Cite

The synthesis, characterization and reactivity of several bi- and tridentate, N-ligated manganese carbonyl trifluoromethyl complexes are presented. These complexes exhibit elongated Mn–CCF3 bonds (versus Mn(CF3)(CO)5), suggesting a lability that could be utilized for the transfer or insertion of the CF3 functional group into organic substrates. Unlike their Mn–X congeners (X = Cl, Br), these Mn–CF3 complexes exhibit a preference for hard donor ancillary ligands, thus enabling the synthesis of 4 N-ligated Mn–CF3 complexes including a mixed-donor tridentate complex using an NNS Schiff base ([2-(methylthio)-N-(1-(pyridin-2-yl)ethylidene)aniline]). Although we have not yet identified efficient CF3 transfer reactions, fluoride abstraction from the Mn–CF3 complexes using trimethylsilyl triflate affords the first stable Mn fluorocarbenes as evidenced by 19F NMR spectroscopy.

show abstract

Section: Reactivitymentioning

confidence: 82%

Synthesis and Reactivity of Mn–CF3 Complexes

et al. 2019

View full text Add to dashboard Cite

show abstract

“…10,11 A review Cyclopropanes from Reactions of Transition-Metal-Carbene Complexes with Olefins has appeared. 12 Complexes 3 are generated in situ from isolable precursors 1 9 or 2 11 through O-and S-methylation and elimination of the respective (thio-)ether. The triphenylphosphine substituted complexes 3a were sufficiently stable to be characterized by 1 H and 13 C NMR.…”

Section: A [2+1] Metal-assisted Cycloaddition Reactionsmentioning

confidence: 99%

Metal-Assisted Cycloaddition Reactions in Organotransition Metal Chemistry

1997

View full text Add to dashboard Cite

show abstract

“…For the straightforward cyclopropanation of alkenes, Helquist et al developed crystalline sulfonium salts, such as 120 (Scheme 38). [74][75][76] Compound 120a is obtained from the sodium ferrate 2 and chloromethyl methyl sulfide in a two-step synthesis on large scale. The complex 119b, isolated in 93% yield after crystallization, is subsequently alkylated with dimethoxycarbenium tetrafluoroborate to furnish the sulfonium salt 120a in about 55% yield.…”

Section: Intramolecular Carbocation Alkene Cyclizations and C-h Insermentioning

confidence: 99%